Sorry about the gravedigging here...
No, there's no way to play the game in a higher resolution. The whole interface is built off of the 640x480 grid, so if you just blow up everything to be suitably huge (which would be a very daunting task) your interface will be shot to holy hell. Besides, blowing everything up would make it hopelessly pixellated. I'd give my first born son to play Fallout in 1024x768, but it isn't likely until the mod community can get its hands on the source code.