I agree with the above poster. Certainly don't go FOR a 2 year old - it's really not designed for them. Most of the games will be beyond their ability, comprehension and even height (unless you hold them up). But if you want to go for YOU, they will be fascinated by all the lights, action and excitement. I wouldn't go for more than a couple hours (that's about all I can take of it personally!) because it's a hard place to nap in, especially if no strollers are allowed. But if you want to go check it out, I'm sure they'd be fine just watching. As pointed out, though, most of the "rides" are virtual reality types and I think a 2 year old would be too small for them. It's not that expensive of a place (and there are places to find discounts online) so you don't have to feel you have to spend all day.
The first time we went, my son was 3 1/2 and he LOVED it. I worried about him having to carry the card around and be responsible for it, but I needn't have worried. I watched him as we were in the arcade area and each game he'd play (I was of course in the same room), he'd put it in the game, then take it out and CAREFULLY put it in his pocket before he started to play. He treated it like a valuable jewel, which to him it was, since it allowed him to play all the games for FREE!