Range: Bow Amazon or Sorceress. The bowa has a drawback if you haven't found a bow that does adequate damage, like Skystrike, for example (but there's this skill called Valkyrie, which if built properly, will help out immensely for the novice bowazon). The Sorceress winds up being difficult to play in Hell due to many monsters being immune to your main attack. Of course, the Sorceress has the perk for Normal and Nightmare of being able to hit Act Bosses quickly so you can farm gear for other characters when she's loaded down with magic find gear. I could also stick the Javazon in here because she's pretty much in the same boat as the Sorceress.
Melee: Paladin or Barbarian. These characters would need some work as the huge numbers of hit points make it difficult without some amount of Crushing Blow. This attribute, however, is available on many low items, such as the runewords Black and Strength (and some of the Unique items also feature this as an attribute). Cannot Be Frozen is also another necessary attribute by mid Nightmare, and getting your resistances built up so they are around 50% would make your characters viable with a few noteable exceptions: The Maggot Lair and the Arcane Sanctuary, if you plan to run solo.
Close Range Casting: The Hammerdin is often regarded as a game breaker., and for good reason. Even without a huge pile of skill boosters, he can still crank out nice area-of-effect damage, he just needs his basic skills built to a certain level. The other popular character for this style would be a Wind Druid, but until he hits level 50 or so, boss fights can be painful.
Minions: The Summoner Necromancer is often overlooked because he's slow moving. On the other hand, with a good investment in his Raise Skeleton and Skeleton Mastery skill, a point the rest of the tree, such as Summon Resist, Clay Golem and a few in Revive will give you a decent army to overcome foes even in Hell. Couple that up with a few points in Corpse Explosion and a point in your Curses as they become available so you can wind up with Amplify Damage, Life Tap, Decrepify and Lower Resist, you will overcome 99.9% of your opponents PvM. You can also pile on all your skill gear, summon your army, swap back to your magic find items and the remaining army will still be strong enough to overcome nearly all monsters.
Now, hopefully I haven't overwhelmed you, but I feel that rather than play what everyone else recommends, you'll enjoy this game the most if you choose a character that suits how you want to play. For some characters, however, you may want to wait until you find items adequate for those particular builds.|||On single player I used a Necromancer - Summoner my first time playing, then when LOD was released I tried out the Druid since he could summon minions also.
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