Iron Man 2 was really disappointing. It wasn't bad, but it wasn't as excellent as the first movie. It seemed like they were pushing too hard for Iron Man 3, so this sequel was half-a-movie and was trying to set up for the 3rd installment.
There was really no sense of urgency, until the very end. The bad guys didn't seem that dangerous and the plot movement felt forced.
I would rather re-watch Iron Man 1 than this disappointing sequel. Lets hope the 3rd one is more exciting.