You'll find that DPS has been sliced up into the different classes, with the highest to the lowest thusly:
1. Mage
2. Scout
3. Priest
4. Fighter
Note: Some may argue #3 and #4, it depends on what type you play.
Within those groups are classes that do higher and lower amounts of damage within those groups (if that makes sense). For example, in the Scout group, you have an Assassin (highest melee damage), Ranger (best ranged attack), and Troubador (lower damage but good buff spells).
Within the Mage class you have Wizard (highest magic nuke), Conjurer (pet and DoTs), and Illusionist (lower damage but good mob-control spells).
Within the Fighter class you have Guardian (best defense but lowest damage), and Monk (good damage but wears lighter armor).
Note: there are many more classes within each of these groups, I just presented a few for example.
Fighters are at the lowest of the DPS ladder, but they get to wear the best armor and have the best Taunt ability. So the fighters job within a gorup is to gain and keep agro while the rest of the group kills the mob.
Monk, Brawler, and Berzerker would be your best bet if you want to be a Fighter that does some (but still not best) damage.
If you are leaning to more DPS, you could go into the Scout group and look at Assassin (best rear melee), Brigand (DPS and agro control), or Ranger (best ranged). Brigands have the added bonus of being able to wear chain armor, adding to their defenses.
Oh, almost forgot our healers that we love so much. On one side you have Templars (best heals, wears plate, but lowest DPS), Warden (heal over time), Fury (good nukes plus heals).
I can't speak to PvP, don't play it.
In endgame there is always a mix of what is needed. Since most raids are conducted by organized guilds, they will have requirements for what they need. Pickup raids are possible.
I always see in chat, "Group LFM - need ____". You can fill that in with "Tank", "Healer", or "DPS". It really depends on who is in the group and what they need to get going. Healers are always needed, but only 1-2 per group. Same with Tanks, only need 1-2 per group. And since DPS classes are plentiful, they typically just call for DPS - first one to answer, wins.
Bottom line, pick a race and class that you have fun with. There may or may not be a need at a particular time for your class, but that's life in EQ2. Play to fill an expected role and you may get discouraged when you are not needed. Play to have fun and your experience will be fun.
Good luck!