You don't say which version of windows you are running, but I guess it's Windows 98/ME. After about a year or so of daily use, I would recommend reformatting your computer...
Back up all your files to a friend's computer (unplug the hard disc and plug it into their computer then copy all your files you want to keep), then format your hard disc and reinstall windows with the disc back in your computer...
Hope that helps
Chris
August 2005