Changing name servers: an idiots' guide please

[#1]

I use my Force9 web space to hold the files for a couple or three different domains which are registered with 1and1. The framed forwarding is causing some inconvenience and so I would like to change the name servers from 1and1's to Force9 to avoid the forwarding.
Can anyone point me to an idiots' guide please?
And is there a charge for making the change?
And will it affect email forwarding?
And anything else I should have asked?
TIA

[#2]

Make sure you leave the registration where it is (renewal on Plusnet is expensive).
Do you want the mail for the domains to be handled by Plusnet?
You want hosting only: see https://portal.plus.net/support/hosting/domains/domainin.shtml

[#3]

Quote from: jelv

Make sure you leave the registration where it is (renewal on Plusnet is expensive).

It certainly is!

Quote from: jelv

Do you want the mail for the domains to be handled by Plusnet?

I don't know. 1and1 currently forward it to my Force9 account where I've got mailboxes set up to do some preliminary sorting. Is it best to leave the current arrangements in place, or are there distinct advantages in moving it?

Quote from: jelv

You want hosting only: see https://portal.plus.net/support/hosting/domains/domainin.shtml

Thanks, just what I wanted. Looking at the timescales, it would probably be wisest to leave it until after Christmas.

[#4]

When you host a domain it automatically moves the mail across. If you wanted it sent else where there would be additional complications. It will mean you will not be dependant on the 1and1 forwarding.

[#5]

Some more thoughts on this...
What do I need to do if, say, I have three domains, all with their files in my Force9 webspace, and I want to move the name servers for each of the domains to Force9? How do I point to each individual index.htm and still avoid any framed forwarding?

[#6]

The domain management help page gives details on how to organise this.

[#7]

There is another way which PN may or may not like. I have hosting by PN but my domain  registration and DNS are else where. I just do a cname for www.mydomain.co.uk to homepages.plus.net