Zems are always active, for 20 years on all servers. They flattened them out a bit in classic about a year ago. If you mean Hotzones, the answer is no. Those come much later.
Yes. Indoor zones > outdoor zones, most outdoor zones are equal (a few notable exceptions), indoor zones may vary wildly. Which are best I'm not going to advertise at this second, although I do have a list. They are the same as Coirnav launch though, if you followed those threads. Options for Selo's are a bit different, I do not have good data on lowbie zones in Kunark, Velious or SoL, by those expacs I'm PLing madly and other factors (# of mobs, HP & respawn time) are more important than ZEM.
Lots of people might know this, but went to CoM today on Selo's. ZEM has been obliterated, mobs were giving less than 1/3 the exp of an equal LGuk mob. (and LGuk actually has a crappy ZEM) Just for reference if anyone from selos pops into this thread.
Lguk is supposed to have a terrible ZEM, but I noticed they give nearly double the exp of DSP. Lguk's ZEM is also fine due to the ease of killing and very high mob density. It is only the slow respawn rate that makes lguk painful. We had a group of 30s last night clearing assassin/supp, exe/cav/sag, and even pulling into the frenzy and hamlord areas, and that was without a chanter pet. The respawns take forever there. CoM has always been a garbage zone, no idea why they nerfed the exp there. It was only really useful to PL in since the mobs have relatively low hp. Also to note, that Uguk was not hit by the ZEM redo, and has absolutely insane exp for lvl 5-20. While kurns, crushbone, and unrest were all hit, they still give solid exp, but PC is still king if you can make your way there and get a good camp.
The hole was the place to be back in the day,and the Crypt of Dalnir had the best dungeon xp in the game if I remember
The hole is the only real option in classic, but chardok and velks are better exp when they open. I've never had the opportunity to try dalnir, but I've heard nothing but good things.
High Hold Keep also had a big bonus, from what I remember the goblin group in the basement always had a waiting list.
