There's not really all that many choices that affect gameplay very much. I'll give the pros and cons of several:

Firey Enchant

Pro: Added damage on a % basis (Fairly often, 40 Fire damage), nifty glow.
Con: % basis favors faster weapons for adding significant DPS.

Crusader

Pro: Minor Heal proc, and +100 STR for 15 seconds is a fair amount of DPS added.
Con: Seems limited to proc every so often (around 1-2 per minute), procs only stack if you're Dual Wielding and both weapons proc.

Icy Chill

Pro: Very useful proc as it limits movement speed (don't remember if it lowered enemy attack speed, too)
Con: No DPS increase, procs every 3 years.


Beyond that, the other enchants are really only done for their visual effects.