Yeah, I kinda figured I'd need a compatibility patch. But do I install Fallout 3 Windows 7 - 8 - 8.1 - 10 Fix, or Fallout 3 Windows 7 Crash Fix - (Easy Install), or Windows 10 - FO3 Optimization, or Fallout 3 Windows 10 Fix, or Fallout 3 Windows 7 and 8 Fix, or....First things first, have you confirmed FO3 runs on your system? FO3 oftentimes doesn't play well with Windows 7 or later, and will crash on startup. If that happens to you, then the first thing you're going to need to deal with is to fix the startup crashes.
And that's just to get the game running. Then I need to look through stuff like the 3 or 4 different "unoffcial Fallout 3 patch" variations, the dozens of pages of bug fixes (some of which fix actual bugs, and some of which are balance changes), the various LAA/4GB memory patches...
And that's all before getting into aesthetic choices.
Whoops, forgot about Fallout Script Extender, wonder how many different versions of that there are!?