The protagonist in the main GTA IV game is named: Niko Bellic (Russian bad a**) In the spin-offs: The Ballad of Gay Tony: Luis Lopez (Gay, I think) The Lost & Damned: Johnny Klebitz (The lost...
Reed Richards , Sue and Johnny Storm and Ben Grimm are exposed to Gamma radiation while aboard an experimental aircraft resulting in their acquisition of superpowers - Reed has the ability to stretch...
If it's a name that exists in the real world and it's obvious that you're not ripping off the other character, then it should be fine. If it's something the author made up, EG, Drizzt Do'urden, then...