Yeah. Go download ZoneAlarm, Spybot Search & Destroy, and AVG free (use google to find them). ZoneAlarm is a firewall which is relatively easy to use, and will allow you to monitor programs that try to access the internet. Anything that you're not using shouldn't be trying to. Don't allow ANYTHING to run as a server if you're not trying to run a service to the public.
Spybot Search & Destroy will also look for things such as keyloggers while it checks your machine for other malicious software.
AVG Free is a free virus scanner that will allow you to scan the machine for anything that people would call a trojan horse or other malicious program classified as a virus.
Also, if the person is using a keylogger, it's probably not very sophisticated. Try going to Start -> Run -> type in msconfig -> Startup and uncheck anything that you don't recall intending to use. There isn't anything in that which could harm your system.
You may also want to do the same for anything that doesn't sound as though it's supposed to be on your machine in the 'Services' tab.