will back off the patches. The list in Add/Remove programs is just entries in the registry so it isn't taking up much space in itself. The fact that the patches can be backed off means there is a backup on your PC somewhere.
I would be careful about deleting things that you don't know. I just got finished repairing a PC on the weekend where someone was trying to free up space by cleaning up files in C:\Windows...
Have you run a disk usage utility to identify what is using the most disk on your hard drive?
http://www.webattack.com/freeware/system/fwdisktools.html
How big is your hard drive? Have you considered getting a larger (or second) hard drive? They're fairly inexpensive.
I'm a big fan of renaming instead of deleting. Reboot and run a test before deleting anything. Make sure you have backups, a boot disk and run/print a Belarc report. It will list a lot of info about your PC including the Windows product key (just in case you need to reinstall Windows).
Some cleanup tips from Grif...
http://reviews.cnet.com/5208-6122-0.html?forumID=44&threadID=2966&messageID=35611
Is it safe to Remove Updates, Patches, SR, Hotfixes from add or remove program list? Do these features just allow you to undo these patches, or are they the patches themselves?
Trying to clean up and get more HD space.

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