Need an Actor

I have read, and have a feeling, that if I can picture someone in particular as (at least) the lead, it will make writing that much easier. The thing is, it will also tend to spin the feel and plot in a certain direction. This is probably a good thing. But it will take some thought before I let it go. The main criteria I have is that they be of the 'right' age (fifties, which means born in the fifties) and be able to play funny (even if they haven't done a bunch of comedies). Here's my list so far:

• Tom Arnold (1959)
• Dan Aykroyd (1952)
• Bruce Campbell (1958)
• Jeff Daniels (1955)
• Bruce Greenwood (1956)
• Tom Hanks (1956)
• Jon Lovitz (1957)
• Robin Williams (1951)

I'm kind of leaning toward Jeff Daniels, since he seems to exude a certain geekiness and mild manner. Robin Williams would probably a little too manic, but then again that could be good. Tom Arnold is probably a little too mild-mannered, as are Dan Aykroyd, Bruce Greenwood and Tom Hanks. Bruce Campbell might be too tongue-in-cheek. Choices. Choices.