That is 110% your choice.
If you like big swords, boomerangs, flails and spears melee might be the class for you.
If you like bows,crossbows, guns and grenade launchers ranged might be the path you want to go down.
If you prefer shooting lasers and massive balls of destruction than you should give mage a try.
If you prefer having your minions take care of all the monsters whilst you sit back and relax you could check out the summoner class.
Of course, just because there are armors and accessories that benefit each of these 'class' types it doesnt mean you have to do one specifically. You could be a mixed class, a gunner and mage, a swordsman and summoner, a magic man and a spear man, an archer and a flailer and many other choices.