Changing Drive Letters

[#1]

I have recently rebuilt my pc, and have ended up with the single hard drive having two partitions identified as C: and E:.  My DVD-Drive is identified by the letter D:.
Call me fussy if you want, but I would like to swap the Identity Letters so that the second partion on the hard drive is D:, and the DVD-Drive letter is Z:. I have tried using the Change Drive Letter process to move the DVD-Drive letter, but have failed to do it, and I cannot get the E: letter on the hard drive changed to D:, while the DVD-Drive clings to it.
Please would someone advise me. My OS is XP Pro
Thanks

[#2]

Right click on my computer icon then manage then disk manage
Right click on the drive you want to change

[#3]

Change the DVD rom to drive R then you can change the E drive to D.
Note: if you have installed any software from DVD when it was 'D:' and you have to reinstall it, it may still look for the necessary files on D which would actually now be on R). Just something to be aware of.

[#4]

Thankyou to both of you. I had already tried OldJims method before contacting the forum, but the DVD-Drive was not visible on the list of drives, so I thought I couldn't change its letter. That time I hadn't noticed the list was longer than what was visible. This time I noticed that there was more list, so I found the DVD Drive and changed its letter. I was then able to change the hard drive partition to D.
Thanks also about that warning about moving the DVD Drive letter. I shall watch for that
Regards

[#5]

One thing to watch out for if you re-install again - make sure C: is available for windows to install on as you can't later change the letter for the system drive.  I found out the hard way