If your game crashes it often means there's a conflicting capture program on the computer, or there's that there's a graphics mod active, or it means that there's a program that adds custom in-game overlays to games (such as teamspeak/mumble overlays), or it could be certain graphics card utilities like msi afterburner for example.
It's a very annoying problem and it's partly OBS' fault, I am going to have to take a look at this soon because I'm just as annoyed as you are with this.