People who set goals for the new year are no way happier than people who don't set goals for the new year. In fact, I'd go as far to say that they are probably less happier than the people who don't set any goals at all.
Lets look at it this way.
Most people who make new years resolutions are looking to either lose weight, exercise more, sort out their financial debt, have a more rewarding job, eat more healthy foods, smoke less cigarettes (or possibly quit), stop procrastinating, be more active, get things done, stress less about smaller things or simply...make more time for themselves to enjoy those smaller (and possibly do bigger) things.
At least 50% of us will fail and in a way, we set ourselves up to fail. The first time we break the resolution we feel weak and therefore feel like a failure. The trick is to fail but not give up entirely.