I grew up on Rallos Zek, one of the servers that was merged with the other PvP's to create the current Zek server. Zek maintains the PvP rules of Rallos.
Be sure to empathize in posting you need PvP class advice.. not normal. Most people on this forum are bluebie, or non-PvP, and very unaware and unexperienced in PvP situations. It's a completely different world from the rest of EQ.
This said, if you're new to it, begin to consider how people are going to fight and the aspects of it. Points to consider (keep in mind PvE is Player vs Environment):
-In PvE, creatures chase you, generally at normal run speed, directly at your current position, unless there's a path. In PvP, players will tend to dodge or run in more thought-out manners.. sometimes, simply more random or misguided ways.
-PvE, MOBs have lots of health. PvP, it's more a matter of piercing defenses than burning through a ton of health.
-PvE, spells are pretty effective most of the time. PvP, well.. it depends on the target and the player.
-PvP, you need to gear up. Skill accounts for much of it, but you won't outdo someone who is all around far superior to you, even if they're hardly a decent player.
Blah. Truth be told, this is going to take too long.. so use the above as example considerations, and go on in such a trend for quite a while.
Since you're new, stick to these guidelines without question until you know more. Ignore bluebies who will tell you differently. Once you're experienced PvP, you'll have a better grasp of exceptions and possiblities.. but these need to be learned personally.
-Avoid pure melees: Warriors, Monks, Rogues, Beserkers.
-Avoid some others at first: Beastlords, Palidans, Clerics, Enchanters
-/who. Not just on zone in, but constantly. Know people near you, and, if you can, all in zone and those in imeediately surrounding zones.
-PoKnowledge, PoTranquility (once you're 46+), Nexus, and Bazaar are your friends. You can't be PvP'd in them. Bind yourself in one of them, perferablly PoK.
-/anon or /role. Either way. Just don't let people see your level.
-(+HP) gear is vital at the lower levels. Not (+Stamina), but (+HP). Look into some jewelry-crafted rings.
Now, for the practical end of this. You want a class that can solo, be effective in groups, and be PvP effective? It's a tricky class to play, but Bards can fill this role. You don't seem like you're new to MMO's. Granted, EQ is already more difficult than any other I've tried, especially WoW, which seems to be indicated by your icon, and Bards only make this worse. Still, if you're up for it, it'd be more doable.
Shadow Knights are another consideration. They're decent soloing, from what I hear.. though I'm not sure to what extent. In groups, they make for fine tanks for all but the most harsh of circumstances. Additionally, they're able to hold their own in many PvP situations.
Much like Shadow Knights, the more magically inclined cusins, Necromancers, would also make for a fine choice. Though perhaps the best choice, I mention it last since they are a caster class.. not only this, but many of their spells rely off draining their life reserves in favor of magical pursuits. While they have other methods to offset this, their combination of innately low defensive abilities mixed with the self-inflicted injuries can leave them vunerable to attack if you don't keep an eye out. This said, their spells are often powerful, especially in PvP encounters, as well as their ability to solo and group.
Good luck.. and don't let things get to you.