PC Fixer is a free Windows diagnostic and repair tool which does a pretty thorough job of scanning and recommending. It’s a small download, but be aware that it won’t run without an Internet connection (probably due to the need to serve adverts while it’s running) which means it’s useless for fixing serious Internet or wireless networking problems.

Nevertheless it offers enough value to warrant getting a cautious thumbs up from me. There’s a useful registry cleaner included as well as a live support service which offers a real person for $19.99 a session who will conduct remote troubleshooting on demand. Of particular interest is the Tune-Up section which looks like it could improve Windows start up times considerably. Definitely worth a look.