Two years ago I went through a similar situation with my PC. Dell was under warranty and had me reinstall the system. It crashed again in less than six months. It turned out the music videos my wife used placed virus"s on our unit.
I utilized and purchased Norton Anit-Virus to no effect. What to do? I am going to tell you what I did to rid myself of these problems without the DownLoading Solution:
1. Do the System Restore to the date you used the computer for the second time.
2. Go to CNET.Com for for Free Downloads.
3. Download the following Programs
AVG
AntiVir
AdAware
Spy Bot
4. Once downloaded run each and every program. This will take a few hours to do.
5. Set the AVG and AntiVir to auto scan
6. Set your yahoo toolbar to include the Norton Spyware.
7. WEEKLY run all these programs manually. Also run
the system disc cleaner and defram.
8. Put the Adaware, Avg, and AntiVir on your desktop.
9. Run C.Cleaner from CNET then erase.
Dell tried to tell me that I had to reprogram my computer some sixteen months ago. I took these steps and repaired my computer in hours. Since then I have not had a single problem. The Avg and AntiVir provide constant protection against virus invasions. Best they are free. At 6am AVG scans and repairs any virus. At Noon AntiVir scans again. Both provide automated updates to virus info.
To crash or restart your computer is a serious step that not need be taken. I implore you to take these steps before you embark on such a mission.