Fixed

use disk partition programme and move your games to non-formatting disk.

you have only C: on your HDD ? i dont really bet.

When I format and I only have one drive, I put all my things on a memory stick (compressing all my files, I have enough with 1GB). You might want to buy something like that, or if you want a lot more room consider an external harddrive.

Those things are completely not the only solution to format, but in some cases (I don't know for you), it can always come in handy to have an extra hard drive, or a memory stick.

I'd just hook it up, and put all your stuff on that one.

If you have one lying around, I assume you know how to install it? I think it's one of the easiest ways to copy that amount of files. AFAIK the unformatted part of a drive isn't big enough, but I don't know nothing about those formatting programs that don't clear your disk or whatever

make a partition for your games and export regedit keys for them too( cd-keys and so on) but paths will change if you only have one partition now and are going to move them, either way its always good to have a partition for windows and another for stuff like games and muzik.

I'm always make my C drive as small as possible (3 to 4GB) and only put windows/software packages on it. That way I can safely format it without a care in the world safe in the knowledge I won't lose any important data.

Also to save reinstalling most games you can simply back up the appropriate registry keys. Then just import them back in once everything is back up and running, no need to reinstall.