In Vanilla I did all content as well as in BC. When WotLK rolled around I started raids there but quit a few months in and came back before Cata and did 10 man LK. When Cata hit I started 10 man progression but quit due to the fact that the guild I was with at the time just was not progressing at the pace I was looking for.
I am not a hardcore raider but it should not take 2 months to learn 1 fight. I am also willing to xfer servers but only to horde as 55 bucks to xfer and change sides I think is a waste of cash.