The 5D is a great camera, it's a solid investment, the noise control is fantastic, it's a quality item. Build up to buying some quality glass to go with it and you're laughing. The 70-200 range is quite usable on FF, 50mm even more so. The 24-105 Lens might be the only one you'll ever need if you don't take shots of things far away.
Out of the two you listed I'd get the Canon 50mm Mk2 - it'll show off the capability of the body.
Out of the two you listed I'd get the Canon 50mm Mk2 - it'll show off the capability of the body.