1. There are normal and special types of servers.
http://eqlive.station.sony.com/library/special_servers.jsp
Guess where it takes you :P
The normal servers don't have any "special rules" per say, The majority of EQ players end up on them. However as to which server is best is up to you. They all follow the same guidelines minus the one listed in the link above. There are lots of people on all of them, most of them shouldn't be to bad. Personaly I'd say my server (check sig) cause well, I like my server.
2. Alternate advancement. Something your charecter can do once they hit 51. Here is a link that lists all the classes and what they get.
http://eq.crgaming.com/archetype/
Now AA is a kinda complicated thing. You can start doing it once you hit level 51 like I said. AA takes a portion of your experienced gained per kill and puts it toward AA "points". You pick the percentage that goes toward AA in increments of 10. 0%, 10%, 20% and so on up to 100%. The experince needed to get one point is equal to that of going through level 51. So as you progress past 51, monsters you kill will give you bacily the same amount of normal xp, but more experience AA wise. In Everquest, the experience (XP) you gain depends on your level and the monsters (mobs). If the mob is higher then you, you'll get a good bit, lower you'll get less.
That's why some people wait till they are 65 to do it, because the XP you get is like you killing that level 60 something mob at level 51, which is a lot. But any way, as you earn points you can use them to buy special abilities. They are all listed in the above link. These abilities are yours from then on, some are permenant (always on) some are usable once an hour we'll say. Depends on ability.
3. Kinda lost on this one. I pass.