It looks like you're new here. If you want to get involved, click one of these buttons!
Secret World (B2P but its a fun game, and you can often find it for ~$15)
Dungeons and Dragons Online
lots of things out there.
Tera Online - PvE/ PvP
Pirates of the Burning Sea - PvP
Lord of the Rings Online - PvE
EQ2 hands down. All of those games combined do not have the amount of content of EQ2. It's solo friendly, you can solo any class to max level. It's group friendly. There are hundreds of dungeons. Huge number of expansions. Excellent lore, great group quests and solo quests and old school EQ1 item quests called Heritage quests. Tradeskills where the stuff you make is somewhat useful, at least in terms of skill upgrades (but you probably wont need until the last tier or levels). Huge number of classes and races, be any race/class combo you want. Lots of end game content, Alternate Abilitite skill levels as you level up. Probably the best housing system in any MMO that is still active. Decent graphics, decent sound. Massive amount of lore available in game and if you pick the right server there are still lots of people playing it. Plus, you do not have to worry about out leveling your friends as there is a mentor system where you can mentor down a to a lower level.
Another choice is LOTRO, which is not as good as EQ2 and has a fraction of the content but it is LOTR, so it's still s decent game.
EQ2 is an old game, but it is totally superior to anything in this thread.
LOTRO, Rift and especially The Secret World would all be good for group play.
Another decent option would be Vanguard, if the older style of MMO appeals to you. Most of the big problems people tend to have with it is finding people to play with, as the pop is still a bit on the low side. If you bring 4-6 friends who are interested, that solves that problem before you even start.
there's enough open world content in VG to level up 4-5 characters to max level without ever doing the same content twice, and you won't have to skip any of it if you're already running around in a group. Grouping is highly rewarded in VG.