just so you know, system restore can be your enemy here. A great deal of spyware/trojans/viruses infect the system restore files. So the second you hit system restore you load even more spyware on your computer.
The best software that I have dealt with for fighting spyware and that I use on all my clients with these issues:
1. Pest patrol 2005 (Extremely fast. Powerful, and picks up everything that other programs miss)
2. AVG-Free. Great software to always leave in your system tray.
3. Windows Antispyware. www.microsoft.com
4. Security task manager. (Allows you to see everything that's running in your computer processes and background and let's you forcefully shut it down and never open up again. Runs similar to hijack-this with a great user-friendly environment.
Load all those programs onto a cd, and you will be able to solve 95% of problems.