I have a ring with Feather 50 points for (I think) 30 sec.

What can I do with It

Can I jump Higher

? ? ?

Feather is a spell that reduces the weight you carry, in the case of your ring 50 weightpoints for 30 seconds. While you have less weight on you you can indeed jump a little higher and run a little faster.

Feather I believe is not a bad enchantment the fact it take of 1 point of weight for every point of feather. Strength on the other hand is well superior as you gain 5X the amount of extra weight in comparison to one point of strength and your damage is also allot better, aswell as fatigue boost.
Feather and strength cost somewhat the same when you enchant an item so go with STRENGTH if you ever decide to.