I've dabbled in High Elves, and really, I wouldn't point a beginner towards them. Admittedly, I wouldn't point a beginner to anything pointy-eared, whether High, Dark, or Wood... but you want what you want, right?
High Elves fight a lot like the Ancient Greeks, I think. There's an emphasis on a phalanx of spears supported by limited chariots and numerous archer units. Because of their Always Strike First rules, you can be fairly defensive with them.
Dark Elves, on the other hand, require a very aggressive style, and do well with multiple small units of crossbowmen combined with very hard-hitting (albeit fragile when taking hits) blocks of infantry. Units like Executioners and Black Guard make anyone nervous.
I know it's not much to go on-- Fantasy really has very little to do with what you actually bring, and more with how you maneuver-- a brick of Goblins can win a fight with even the most elite troops if they flank them, after all.
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