Never played 1, and couldn't play far into 2.

I then played Makai Kingdom, which blew Disgaea 2 out of the water. I loved it so much.

Disgaea 3 was awesome as well. Mao is one of the funniest protagonists ever. The only big issue I had is a lot of the last few maps were more about figuring out the Geo Panel puzzle to win the battle then actually playing an SRPG, though it's only a handful of dungeons that do it. On a whole though, it's definitely good enough I'm eagerly awaiting Disgaea 4, though I wish they'd give me a Makai sequal on PS3 sometime.