Wait so are they playing Blackjack or Texas Holdem?
If they're playing Blackjack, one of those cards should be the other way. If they're playing Holdem we'd need more information to tell if going all in would be reasonable.
No, it's almost exactly a coin flip. AK has so many outs, flush potential, straight potential. The pair of twos has exactly two cards out of the whole deck to improve.
Almost exactly, but not quite. Difference is a pair of twos is already the winning hand. The AK HAS to have one of the other aces or kings drop, or get a straight or a flush. Twos will win without any help.
Odds of deuces winning on an all in pre-flop are 52% to 48% against a big slick, but that's exactly the type of odds that make sure casinos always make money gambling. "Not quite a coin flip"