In battlegrounds before level 70, you might find that you aren't so much being outplayed by other classes, as by twinks. Players with lv 70 mains to fund lower level characters with the best gear and enchants. Unless you really enjoy playing against the odds, i wouldn't bother with battlegrounds before endgame.
As far as spending talents for solo play goes, the retribution tree is what you should be going for. You'll find a lot of talents here that reduce the cost of offensive spells, reduce the cooldown on them, and generally increase damage and critical hit chance.
You're level 28, so you have 19 points to spend. Here's where i would spend talent points at this level (all of these are Retribution talents):
5/5 Benidiction, less mana spent is less time drinking between fights. And you don't want to run out of mana during a tough fight with an elite!
2/2 Improved Judgement, judgements are a big source of damage, so being able to use them more often is fantastic.
3/3 Improved seal of the crusader, 3% extra crit chance translates into 3% extra damage, a no brainer talent. This judgement should be on every enemy you fight.
5/5 Conviction, more crit = moar damage!
1/1 Seal of Command. This should be what you use after judging crusader on an enemy, with a very slow, high dps 2-handed weapon it's the most powerful seal you'll ever get.
3/3 Pursuit of Justice. Leveling involves running around a lot, so moving 15% faster makes it 15% quicker! The spell avoidence is just gravy, especially Paladins can have trouble with caster mobs.
After that, just move down the retribution tree picking up everything that adds damage. After picking up everything useful, you could move into the holy tree to improve healing, or go into the protection tree to pick up precision and Blessing of kings.
Edited, Jul 19th 2008 12:25pm by ArtemisEnteri
Edited, Jul 19th 2008 12:25pm by ArtemisEnteri