The one problem with Battle of the Worlds is that it tries to be a lot of things and doesn't quite pull any of them off. It tries to be a regular Italian space opera. It tries to be intelligent science fiction. Claude Rains definitely tries to make it a monodrama.
Unfortunately, the script doesn't let it be any of these things, and Claude's overacting makes you almost want to take a swing at the poor guy...I'm hoping that he had a good time while he did this movie (since it was really his last film), because it really was fun to watch him in this movie. His performance as a cantankerous, pajama-wearing, genius of a hermit who can answer any problem through calculus just didn't help things, and his character's attitude toward everything that wasn't math or himself make me wonder why his co-workers didn't lock him up in a rubber room.
The effects are a little on the loq quality side, even considering the general quality of Italian Sci-Fi movie SFX, but they don't really detract that much from the movie.