Hl2.exe has stopped working - (Oh yeah, that fun error)

So I haven’t opened steam in months, and I got all these new updates and such. Garry’s Mod doesn’t appear to be working now for some strange reason. I open it, it shows me the loading screen, then right before the main menu pops up, BAM! It crashes to the desktop giving me the “hl2.exe has stopped working” error. Any ideas how to solve this? I’ve reinstalled steam twice and deleted the client registry… and verified the GCF.

I’m also on Windows 7, with UAC off.

EDIT: Could it be because TF2 wasn’t updated? Trying that now…
EDIT 2: Nope, still not loading. Help please?