I disabled auto starting for it so now it won't crash. But it did freeze after about an hour of defrag. I think it might be missing thermal paste or something. I'll send it to a specialist if it ever randomly crashes. I'm getting a gaming rig soon so all is well.

Destructoid, go to C:\Program Files\Steam and delete all the contents, except for the SteamApps folder and Steam.exe.
Then just run Steam.exe and hope for the best.

The folder would be Program Files (x86) if you have 64-bit though.

You could try running a Malware Scanner or anti-virus to see if there's anything else sketchy on your computer that could be causing an issue.