Question: Does Microsoft Virtual PC have any scripting capabilities? I'm trying to automatically launch a web browser inside the VM and have it go to url specified by a parameter.

Answer: 
For "basic" viruses you'll want to boot up in safe mode and delete the executable (you could use Process Explorer, or task manager from Vista onwards, to locate the file), but for more advanced types I always find using Sysinternal's Autoruns to remove their ability to start up (along with any helper applications they have) does it. Anything that lives through that might take a little more poking to fix.
99% CPU you say? Sounds like a poorly coded keylogger. Try checking `msconfig` for suspicious startup entries first and foremost. You can use [Process Explorer](http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx) to find information about the process itself, and if you have the location of the program, kill it with process explorer then delete it. It's wishful thinking to assume something this simple will work, but it's worth a try. If that doesn't work, back up your friends documents and do a clean install, for me there is no safer feeling than a fresh OS install (if it's a possibility). If that isn't an option, download [Avira](http://www.avira.com/en/pages/index.php) and [Malwarebytes anti-malware](http://www.malwarebytes.org/mbam.php) and do a full system scan **in safe mode**, that should take care of it.