To those who want to start watching this: in my opinion, 2 and 4 are the best seasons. 1 is good too but it's okay to start at either of those if you don't feel like watching all episodes just to get to the recent ones.
Season 4 is my favorite one, too. Even though it was cut short, I loved the ensemble they had with all of the doctors during the competition. Made for some great humour, and some good drama at the end. I think they succeeded where other shows failed with the limitations the the writer's strike imposed.
So, yeah, I never condone skipping seasons or even episodes, but look forward to season four, if you're just starting.