Hi curlylad. You could spend quite a few hours trying to find and eliminate anything that is on there, especially if it's as bad as you say.
Seeing that it's brand new it may be quicker to use the Restore CD (If it has one) and reset the PC back to factory condition and start again.
This time make sure he has the necessary protection of a good anti-virus program, also the programs you mention in your post.
Good luck. j.