gbrocks - I'll answer your query. Age is a factor, but depends on how fit you are. Talk to your local careers office, be prepared to be swayed to different regs. If you can keep up with the younger lads then I dont see the problem.
I think you have till 33 to apply for the army, not positive on that, but thats another thing you can ask.
Good Luck - Be sure with your decisions either way.