I installed fallout 3 GOTY from a disc, I played about 2 hours while it was running fine. I decided to look into modding (my first experience modding anything), and it started crashing. I disabled all mods and expansions, so I was running Fallout 3 vanilla, and it is still crashing on me. I tried Googling it but everything I found was about crashing on a New Game or it would run fine when mods were disabled. Any ideas what could be wrong?

PS I followed instructions on YouTube from DansGaming

Thanks!

Ah I figured it out. Apparently I missed downloading the UI Hotfix alongside Darnified UI

Glad you found the issue, mods can cause a lot of issues if installed/loaded incorectly. Are you using a mod manager? If not I highly suggest that you do and also make sure you download the wonderful mod https://loot.github.io/ which will manage your load order for you.