Windows Multi-boot question....

[#1]

I have a primary hard disk partitioned into 3:
1st = Original Windows XP installation (but having issues - possibly corrupt driver causing irregular crash/restart - no idea what the issue is, too many applications, utilities and rubbish installed, but getting more regular....)
2nd = Odd Data (not primary data - that's on a discrete Hard Disk)
3rd = New (as of today) alternative Windows XP installation - installing apps & stuff as per 1st partition, waiting to see when issue occurs.
Also, have installed Ubuntu (originally for testing purposes, but now used more and more) via one of the "weird" methods - e.g. installed via (original) Windows as an application (appears in Windows 'Add/Remove Programs') with Ubuntu virtual disks (8GB worth) on the discrete Data Disk, which means that a boot sequence is currently as follows (I believe):
-> BIOS -> Primary Disk MBR -> Partition 1 (e.g. C:, original Windows installation) -> boot.ini, which has the following:
[boot loader]
timeout=5
default=multi(0)disk(0)rdisk(0)partition(3)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional MAIN" /noexecute=optin /fastdetect
multi(0)disk(0)rdisk(0)partition(3)\WINDOWS="Microsoft Windows XP Professional ALT" /noexecute=optin /fastdetect
c:\wubildr.mbr="Ubuntu"
So, to boot Ubuntu, the "boot.ini" in the original Windows install points to a file in the root of that partition, and I then get the familiar Ubuntu grub boot selection screen, albeit only one option (into Ubuntu). Otherwise, I choose original or alternative Windows XP installation. Also, as far as I can tell, there is no "boot.ini" in the "alternative" Windows installation on the 3rd partition.......
I as considering in the near future, to go Windows 7. I always try and do a "clean install" when upgrading OS (which I have to do to go from XP to 7, anyway). I have issues with the original installation (on partition 1) of Windows XP - so it makes sense, during the "upgrade" to Windows 7, when doing a clean install, to wipe/format that 1st partition, and install Windows 7 there. Question is, what will happen to my multi-boot set-up? Will *any* of it be in place afterwards? Even if the Win7 upgrade "makes a note" of the boot.ini and reproduces it, the "c:\wubildr.mbr" file won't be there, as the partition was wiped....
I use Aronis TIH2009 to make disk images, so can pick up files out of archives, or restore if everything goes really pear-shaped, but it would be nice to be forewarned as to what to expect to happen, and perhaps have a way to resolve any issues created by the Win7 upgrade/install.....
Any advice gratefully received....
Thanks,

[#2]

Windows will merrily ignore the presence of any other OSs and rewrite the Master Boot Record when it is installed, thus cutting off access to the other OSs. All will not be lost, although the solution is a bit involved.

[#3]

Also, the Master Boot Record for Vista and Windows 7 is configured differently than for XP and prior versions of Windows.  So, for example, the boot.ini file is no longer used and the process by which you edit the Windows 7 equivalent is a bit more complicated.  After you install Windows 7 you should still be able to boot to your XP installations but I think you would have to recreate the XP-style MBR if you ever decided to uninstall Windows 7.   

[#4]

@Denzil - Unfortunately, the linked resource seems to only refer to "standard" installations of Ubuntu - e.g. where you allocate "real" partitions to Ubuntu, and install the OS into them - but my install is the one where Ubuntu is installed under Windows as an application - that is, it seems to add some boot stuff (adds a line to 'boot.ini', and puts a couple of files in the root of the Windows partition), and the Ubuntu partitons are actually "enclosed" within a couple of (very large - 14.7GB in my case) Windows folders somewhere else - in my case, on my 2nd HD (which is the HD I use for my data). Reading through the information in the link did remind me of the install method I'd used ("Wubi" - I'd forgotten what the Ubuntu under Windows project was called...), so I've got a starting point for more research.... thanks.
@ReedRichards - I've found "EasyBCD" utility, which I believe assists in editing the Windows7 boot options/order functions.... Anyone used it and can confirm it's "integrity" (i.e. won't trash my system..??!!) ?
From the information gathered so far, I'm hoping that as I am using Wubi, recovery *might* be relatively simple, i.e.:
- recover the boot files that were in the root of the original Windows XP partition from my Acronis backup (e.g. "c:\wubildr.mbr" and "c:\wubildr") and put them in the root of the newly created Windows 7 partition
- use EasyBCD to edit the Windows7 boot options, and add a link to ""c:\wubildr.mbr" as the boot option for Ubuntu (e.g. as per the entry in "boot.ini" shown in the original post). This is the bit I'm unsure about - I don't know whether the new Windows7 boot facility supports simply pointing at a file....
Having just downloaded it, off to test EasyBCD on my Windows7 Beta machine.....
Thx

[#5]

Erm, I don't know much about Wubi, but it might be simpler to install W7, then do a new conventional install of Ubuntu on its own partition (i.e. boot from the install CD rather than run it under Windows). The Ubuntu installer will detect the presence of other OSs and offer to repartition the hard drive accordingly. It goes without saying that your data should be backed up, of course before you try any of this!

[#6]

Unfortunately, Ubuntu is a "2nd OS" for me (through necessity of certain applications running on the XP install......) and don't get a lot of time to explore it - albeit, I've done quite a lot of customisation of the Ubuntu environment that I wouldn't want to re-visit (I'd need to remember what I'd done, as well as research again how I did it!!).
I think I'll have a go with the method I mentioned, as I found a similar 'solution' mentioned on the web - however, when I tested EasyBCD earlier on Win7, it had an option to add a Wubi boot to Windows 7 - but the link to the Wubi MBR file was wrong, and I couldn't see a way to (simply text) edit the BCD file to change it to the Wubi MBR file name as located in the root of the C: drive (or where it was/ should be, once I copy it back there....). I guess I could try and rename the Wubi MBR file, and put it in the location specified by EasyBCD by default... we'll see.
Everything (sys disk and data disk) is backed up using Acronis (regularly - probably not as regularly as it should be...), so my data (and original system installs) are safe - but if it comes to it, as I'm using Ubuntu more nowadays, I might bite the bullet and do as you say - a "proper" install of Ubuntu into it's own partition(s) onto the System Disk after Win7 install, and then see if I can re-visit my "customisations".....
Thanks for the feedback...

[#7]

Quote from: Denzil

Windows will merrily ignore the presence of any other OSs and rewrite the Master Boot Record when it is installed, thus cutting off access to the other OSs. All will not be lost, although the solution is a bit involved.

Couldn't agree more. Windows loves seperating you from the competing free *nix OS's you may have on your HDD. I learnt that many years ago when I regularly tried out various OS's on different partitions.
If it helps, I used to use XOSL as a boot loader. It was virtually bomb proof and could even keep windows tame on its own partition. I'll warn you now though should you use it the setup can be devastating to existing partitions if you get it wrong. Something about dedicated partition to install it on ALWAYS selects the c: partition by default and unknown to me at the time you use the page up/down buttons to choose the empty partition you want it on.
Frankly though its now just far easier to use a VM for every OS you want to use. Saves a LOT of hassle! http://www.vmware.com