First off Paladins are melee characters by nature and by default will be involved in close hand combat. You will want your Paladin to have good defense against physical attacks and a good shield (as the paladin can use it as a weapon). Elemental attacks are not as much of a concern IF you spend a point into the proper auras.  A successful paladin will be one who can switch between the many different auras to buff up weaknesses during an attack.  Manna should be raised a little bit but not by any means focused on.  As your paladin will be a melee attacker he is VERY SUSEPTABLE to curses. Be sure to give your paladin a couple of points into cleansing (2 to 3 but no more).  Lastly, pay attention to curses and negative auras placed on your character and how they affect him.  A deadly curse for melee characters is thorns followed by decryptify (thorns can kill you QUICK).

Offense:

Now that you’ve gotten to know how the paladin works defensively its time to talk about your offense.  The paladin auras are a very good source of power as they require no manna (except prayer) to operate. The downside is that you can only have ONE aura operational at once.  So learn which auras you will need and hotkey those auras.  By combining use of your auras and combat skills your paladin can make quick work of any foe.  Since Diablo II gives you two weapon/shield configurations leave a ranged attack option open so you can take out troublesome magic users with out trying to chase them down.

Crowd Control

The way to death for any character is blindly charging into combat as you will get surrounded.  Every time you get hit your attack is interrupted, and if you are surrounded by 5+ enemies that’s 5+ hits at once (which makes you just stand there stunned for a second). The result, Your Death.  Crowd control for the Paladin is accomplished by separating mobs into groups of 1 to 2 then attacking with zeal.  Your aim is to have a group small enough that your paladin will cut through them by the time the next group catches up with you.  Another option is to have a ranged weapon as a secondary option to handle cursing monsters (especially when cursed with Iron Maiden as this curse only reflects Melee attacks, not ranged).

Boss Strategies:

Beating the bosses of the acts is achieving a balance of defense vs. offense.  Don’t be afraid to run to catch a breather or run to town for supplies.  Learn the movements just before their most deadly attacks and dodge accordingly.  For the most part each boss will like an element, build up your defense for this element and strengthen your damage output. The longer the fight drags out the tougher it will be.

Act one boss: Poison

Act two Boss: Cold (keep thaw potions handy)

Act three Boss: Lightning, Poison, magic.

Act Four Boss (Diablo): Fire, Lightning (Strong Lightning)