So, if you're like me, you bought this on GOG because it was supposed to work MUCH better than the Steam version. Well, whenever I would click that "Play" button on the launcher for FO3, I was given an instant crash. No intro movie, no menu, just crash. Upon further research, I noticed the Fallout.ini didn't match up with everyone else's that were mentioning fixes. For some reason it barely had any text in it. So I found a fix on Nexus, AND IT WORKED! Hopefully, this will with you too.

Apparently I can't post links, so Google Search:
"Windows 10 - FO3 Optimization Nexus"

and click the appropriate Nexus Mods link

then download the INI Files under the "Files" Section

This is specifically the INI Files, that have the correct setup. Replace these over your old ones in: Documents\My Games\Fallout3

!!!MAKE SURE TO BACKUP ANY OLD FILES YOU REPLACE!!!

War. War never changes.

It worked! You sir are an absolute legend! I had refunded my steam copy of the game because I couldn't get it working, and was ready to refund my gog copy when I couldnt get it working either.

Legend.

You are the best guy. It has been years since this game has turned on for me. this is awesome thank you.

Thank you for this topic, I was already losing any hope to launch it.

I had the same problem, thank you for the thread