Windows XP

I'm trying to do a system restore, to a point about 10 days to 2 weeks ago, and the computer won't let me!!

I go into the system restore file and select a date to restore to. It says it's restoring, then the computer restarts. A box comes on the screen that says the computer was unable to restore to Feb. 10 (or whichever date I selected), and no changes were made. Click on home to select another date to restore. I tried at least 6-8 dates, the only one it would restore to was yesterday.

As an alternative to system restore, I'd like to figure out how to uninstall "PC tools Spyware Doctor with Anti-virus".

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My problems started a week or so ago, when the computer would suddenly slooooowwww waaaaaay down...and sometimes freeze, so that turning it off was the only way to get it to (maybe) do anything.

After a few days of that, it suddenly decided to restart one day...I was in the middle of something, and it suddenly shut itself down, then turned back on.

The erratic behavior continued for a few days...working pretty well part of the time, then slowing down or freezing.

Yesterday it restarted itself again, and when it came back on there was a message that said it was recovering from a major error. It said that there was something in the computer that caused it to shut down. Perhaps new hardware (we haven't added anything new or different), or new software. The only thing I can think of is that we got an email on Feb. 9th, saying there was a new release of PC Tools Spyware Doctor available, and we could get the updated version as part of our subscription....so I installed it.

I think the problems started a day or two after that...help?