As for weapons, on level 1 just use the ember rapier you get in the tutorial quest. Starting at level 2 use thaumaturgy staffs, preferably that boost both your elemental lines as well as giving lore in one of them. If you're unfamiliar with them, search the auction house for "thau" and they'll come up.
Starting at level 2 you won't be swinging weapons. Instead, you "nuke" stuff with damaging ray spells, and later cast area-of-effect (aoe) damage-over-time (dot) spells. Also starting at level 2 you can use mind control to make enemies fight on your side, greatly reducing the attacks coming your way as the rest of the mobs get busy killing your slaves. At later levels you use instant-death spells that don't do damage but instead just drop mobs in their tracks.
Niac's Cold Ray, Scorching Ray, Frost Lance, Lightning Bolt, Prismatic Ray, Necrotic Ray, Polar Ray
Niac's is your bread and butter at level 2. It starts to lose its effectiveness around level 4, but that's when scorching ray kicks in. As an alternative to rays you could go with splash damage spells like scorch, acid blast, cone of cold and fireball. I've never been a fan of splash damage spells but I've seen them be extremely effective.
Good AOE DOTs:
Acid Rain, Wall of Fire, Ice Storm
Charm Person, Charm Monster, Dominate Person
Dominate Person is particularly nice, especially at the level you get it. It works well on kobolds, hobgoblins, dwarves, elves; anything humanoid that's roughly your size. It won't work on ogres or trolls, though. For non-humanoids go with charm monster. "Charm" spells are short duration control (around a minute, maybe) and they attack stuff near them. "Dominate" spells are long duration (several minutes) and the dominated enemy will follow you around like a hireling. You can dominate multiple enemies, eventually ending up with a dozen slaves who swarm any new mobs you come across. I dig doing that. Starting at level 2 you can use charm person; sahuagin aren't people but cultists, kobolds and hobgoblines are.
Web, Hold Person, Hold Monster, Otto's Sphere of Dancing (dball)
Web is the greatest thing since sliced bread at low levels, especially if you cast it and wall of fire at the same spot at the same time. Enemies get stuck in the web and burn to a crisp.
Phantasmal Killer, Finger of Death, Prismatic (sp)ray, Trap the Soul, Power Word: Kill, Wail
Insta-kill spells are pretty high level so you won't get them for a while, except for phantasmal killer. PK isn't the best insta-killer for a pale master but it can be fun to play around with in low level content.