Here's the deal:
Log on as yourself, get on the Internet, download the "Hijack-This" program (search google with that). Get the program, open it up on your desktop, hit scan. This will list all the stuff that starts and runs during booting. If you don't know what to check-mark to FIX, then save the log, open it up, copy-and-paste-and-post the log here. I'll be here.
While your at it, check to make sure you've defragmented. (If you wanna do that, go to "Start"-"Control Panel"- make sure its in category view (the simple style, NOT classic view. Click on Performance and Mainenance. Click the last slection with the green arrow box thing. "Rearrange items on your hard disk to make programs run faster." Click this to make "Disk Defragmenter" come up, choose the hard drive to defrag and click the "Defragment" button.
There may be more to your situation. Please post me back.