Welcome!!!
Teva, Bijou, and Epith are the most populated servers - Teva is the oldest, I think, and is a high level server mainly. Legal and Cypion are new, and probably have more of the lower levels. I would go with Epith, just because Raini seems pretty willing to pull you in and help you learn the ropes.
Each class has it's own advantages, but cleric is probably the slowest to level unless you party all of the time. Archer is a good choice, can pull mobs from a distance, and the one I play levels fairly quickly. Make sure you learn product making skills right away - I recommend scrolls and stones if you are looking to make in-game money. That will help you buy better gears from other players faster. Good luck and have fun!!!