You could try disabling some of your starting up programs, if you have a lot that is. A lot of progs out there (yahoo, AIM, etc.) and not just limited to messengers, will automatically start upon booting of your system, and if you have a few of them, they can chew on your resources and cause poor performance. You can go in to MSCONFIG and disable them on startup, so they only start when YOU want them to.
Also, virii and spyware, adware, etc. will cause poor performance as well. Do you have good spyware/virus software? If so, run a complete system scan. You can also disable some of your active X controls in the "manage add-ons" menu in the toolbar for IE. If you try some of these things and no luck, then it's probably time to back up your hard drive and reformat and re update the Operating system.
Hope that helps you some
