I need help

[JackoliciousLegs]

Macs will have viruses aplenty when a lot of people start using them.

want to write zeros and start from scratch?

I am just speechless... no wonder you have more posts than me...

Feersty, find the process that's taking the CPU usage. Try creating a new user and logging in with that. See if that new user still has the high CPU usage. Run msconfig and see if there's anything that's starting up with the machine that looks funky.