Microsoft XP acting up. Need help

Sorry, WINDOWS XP........I was reading some ways to speed my computer up. And i read articles that said you can clean your registry. Well i dont know what i did. All i know is when i try to open excel, or try to download updates it says "the features you are trying to useis on a CD-ROM or otherremovable disk that is not available. Insert the microsoft office xp professional with front page disk. I knew messing with the registry could be harmful. Now the computer is even slower and it freezes. We have kaspersy anti virus and it updates just fine if that matters? Anyone can help me, it would be appreciated. I know im stupid. Thanks

Sure i will sure you out with this issue try to re-install Microsoft Office XP and try to check out this link too hope your problem would get solved

http://forums.techarena.in/troubleshoot-98/875911.htm