In Fallout 2 there are at least three occasion early on that NPC's will teach you how to fight (improve your Unarmed and Melee skills). I got them both up to almost 100 by just letting them teach me
Two tribals in your village, and then a guy at the Golden Gecko in Klamath.
To finish the Temple of Trials rather easy, you can tag Unarmed or Melee and beat the crap out of all those insects on your way to the last fight, or you just run passed them all (some will engage in combat, just walk far away enough from them, our of reach/sight and then exit combat). Downside to ignoring the bugs is the XP from killing them.
The last fight is against a human opponent. If you have a good Speech (or Intelligence too, IIRC?... do I?) you can reason with him and skip the fight.
Melee is an awesome skill, though versus a bunch of spread-out slavers with burst weapons................ you are dead. So you'll need to know how to shoot, it's also fun to burst-kill people.