PVE raiding server/faction

Hey guys I'm completely new to this I just got the client and an account cause I wanted to play WotLK as it was back in the day. Just wondering what server is best for Raiding/PVE. Best population and pve focus overall. I don't want to start a character and figure out I made a mistake of going to the wrong realm.

Thanks for your response in advance :)

P.S: I don't care about levelling bonuses or dungeon finder I just want to play mostly or as closely as it was back in retail days :).

Kind regards

Wiskie