So I noticed today that all of my programs were running extra sluggishly, so I rebooted hoping that would help. Everything seems to be running at decent speed, but a new problem presents itself: when I log in, I get the wallpaper, but explorer doesn't boot up. So I tried going into the task manager and manually running explorer.exe. It comes onto the screen for a maximum of 5 seconds, and then disappears. So now I have to run all of my programs through task manager. I've tried a system restore to 2 days earlier, I've ran an AVG and Spybot scan and removed all spyware (no viruses presented themselves), and I've uninstalled programs recently installed that I thought might cause the issue. All of them unsuccesful.

So, any thoughts? Any help would be much appreciated.