I just got this problem today. My game will launch and enter it's usual "loading" screen where it shows a picture of 2fort or upward, then crashes (hl2.exe is not responding) as soon as it reaches the game menu. I've already tried:
-Verifying my game cache
-Uninstalling/reinstalling HUD
-Reboot
-Reinstalling TF2
What else can I do? Any help is appreciated.