Most Helpful Guy
Go on a date or two with both of them. Pick the one you like better.
Oh, don't fucking put Mike on some pedastal. He's just a guy, 1,000's more like him. If you really aren't sure you're "good enough" for him, date Danny.
Most Helpful Girl
Personally I'd pick Danny. As you said, Danny is always up to talk and it seems like Mike is just too busy. Danny seems like a good guy.