computer problems again

[GhastMaster]

For a few days I have bee getting intermittent freezes; the machine needs to be manually shut down. Now it won't boot up at all. The lights come on, and the optical drives go through their little light show, but then everything stops. I never even get to any of the bootup screens.

A week or 2 previously the system hung up when shutting down and lost the internet connection. I ascribed that to updating my AVG software. After removing AVG and running AVAST instead thatttt problem seemed to disappear--I don't know if that is related.

What could be the culprit and how and where do I start?

Thanks.

Have you tried booting from your xp cd? That's pretty strange. I wish you luck.