Hey Laura,
Looks to me like you have a "memory leak". Without getting into huge detail and getting all the specs on your computer, there are a few things you can try first. If these don't work then PM me with your computer specs. In other words, what type of processor you have, amount of memory, operating system, mouse type, keyboard type, browser you use and what chat programs you use.
First try the simple stuff.....Update all the security fixes that Microsoft has. If your computer is less than 6 years old you shouldn't have a problem. If you see any updates that say "NET framework" those are what you need first. DON'T update to IE7. If you need info on how to not update certain updates just ask, I'll give you the info.
After you do the Windows update, do a simple disk clean up on ALL drives you have. Many folks have two hard drives these days. Then after that clear your cache on your browser. After that do a Disk Defrag, restart, do another Disk Defrag. So to try the simple stuff first:
1) Update Windows (avoid IE7)
2) Clear temporary files and cache in your browser
3) Restart
4) Do a Disk cleanup
5) Do a Disk Defrag
6) Restart
7) Do a Disk Defrag again
If those steps don't work or your not sure how to do any of those lemme know
Edit addition: By the way if you already have IE7 that is where your problem is. If you uninstall IE7 and then follow the above steps you will solve your problem. The best browser out there right now is Firefox, it is very secure and glitch free. There is also Opera, ya might want to ask Muz about Opera for a browser, he uses that one.
Blessed are those who can give without remembering and take without forgetting.
I guess I should install spysweeper huh? especially since I already have it 
