Computer going downhill!

This is about the 3rd post published about what's been named 'Lappie the Laptop'. It's been said that it needs more memory, the internet has been surfed for it a new 2gb memory stick, but it's the screen that needs looking at. Because I could be in the middle of watching a video, working on the Phillip Schofield fan community or replying to a tweet. And all of a sudden, the screen would go funny, which means I end up taking the battery out and find Windows Error Recovery comes up again. There's even been cases where it's reset itself to the 31st of December 2002, 23:15. And to my knowledge there's no viruses or harmful software on the computer to be seen... So I wonder if it's just one-off errors happening