Rangers are definitely a good class to start with for the very reason mentioned above: that they're Jacks of All (well, Most

) Trades and are definitely not complicated.
They do a bit of just about everything from damaging, defense (blocking attacks, healing themselves (and their pet), and some condition (blindness, poison, that sort of thing) removal), placing conditions on their foes or interrupting their spell and skill use, plus a few other things that are unique to them - like their pet (if you're playing Prophecies, keep the pet you get from the Ranger tutorial quest 'til you meet Ranger Nente again after moving out of the tutorial region) and setting traps to lure their enemies over (mainly to place conditions on them and help keep them bunched up).
How good Rangers are later on in the game really depends on how good you get as a player, especially with interrupting skills/spells (takes timing and a fair bit of knowledge and experience to know which monsters, or players in PvP, are worth disrupting, other than the one that you've been targetting with damage), trapping (and the related player skill of pulling apart groups when multiple groups of monsters congregate in an area), and pet mastery (there's a huge difference between taking the skill that lets you have a pet and, as standard, the skill that lets you heal and resurrect your pet, and actually having that pet be useful as more than just a minor distraction, at least later on).
One thing that hasn't been mentioned about Rangers, though, is that (once you can add Henchmen to your party) they tend not to be a priority target for monsters. Since Rangers aren't right in the monsters' faces like Warriors, Dervishes (Nightfall) and Assassins (Factions) are, and their armor is significantly better than a spellcaster's (especially if monsters take into account the bonus armor rating Rangers get against elemental damage), monsters will mainly go for the other players. Still a good idea to bring one of their blocking and escape skills, of course.
