Well, here's what I do when Steam (or any other application) crashes:
1. Try doing the same thing again. If it doesn't crash again, it was probably a one-off.
2. If the problem persists, google it.
If you can find forum posts where people offer fixes, and it has positive responses, it might be worth giving it a shot. I found several of these simply by googling "steam bootstrapper error".
Here, I'll even throw in a freebie for you: "If you right click on steam.exe and hit troubleshoot compatibility, then use whatever recommended settings it has, it should work for you."