its safe to abandon all pre-tbc quests. The only one you might want to do is the onyxia quest line so you can go in and kill Ony....we do it when we are bored...so far we have 8 man Ony, that was a fun fight...the priest died 1/2 way from DB, leaving me to heal the remaining 7 guys

like Nef lor....but for old timers....theres still nothing cooler then the whole raid riding through SW.....then hanging ONy's head on the entrance of SW

So "Yau yeng". When i was lowbie...i always imagine one day..when i can ride tru SW and hang the head