I wasn't that impressed with the first Hangover purely because everyone had hyped it up that much and when i saw it, it wasn't as funny as i thought it was going to be.
As for The hangover 2, it's not worth paying to see it at the cinema. It's exactly the same as the first one, just set in a different location. I thought the film adverts before the actual showing were funnier than the actual film itself tbh, but hey everyone to their own opinion.
If people liked the first hangover, then they'll most likely enjoy the 2nd one.