I have tried EVERYTHING I know of. I've uninstalled all mods, uninstalled the game, reinstalled the mods and reinstalled the game, uninstalled it again and tried the game without any mods, it ran just fine not too long ago, but after installing mods and playing the game, it won't even get to the logo without crashing. If there is ANYTHING that I could do, please tell me.

When you reinstalled the game, you deleted the FNV directory manually after removing local content? Ill also add to make sure you backup then delete this directory: C:\...............\Documents\My Games\FalloutNV

If you didnt do this, then reinstall the game and try it with no mods first. Don't even think about mods until this issue is resolved.