Jesus
Gandhi
Joseph Smith (So I could call him a fucking lunatic in person)
L. Ron Hubbard (Same as above)
J. Robert Oppenheimer
Richard Feyman
Mike Patton
Dimebag Darrell
Einstein's biggest involvement with the bomb was convincing Roosevelt that the Germans were working on nuclear weaponry and we needed to beat them to the punch. That was his only direct involvement with the Manhatten Project. I've always had a pedestrian interest in the development of nuclear weaponry, and Oppenheimer was at the head of it all.
I didn't list Einstein simply because I didn't feel like being redundant.
Gandhi, because he's one of the most insipirational figures in human history. I suppose I'd also add Desmond Tutu to the list, now that I think about it.
Myself in 20 years so I can see what I could do better.
Myself 5 years ago to tell myself what myself told me.
Also if anyone needs to shoot anyone in the head, they could always hire me, I am a qualified sharpshooter with an M16A2, an expert with a bayonet, and an expert with grenades. Plus Im pretty stealthy(mostly the pretty part).
Who else would I pick? Hitler was an asshole, don't want to meet him. Can't say I give two shits about ghandi. Einstein would probably make me feel more stupid then I actually am. I really don't care much for anything before 1939. So yeah, it would either be him or Gene Roddenberry.