Hi experts!

I've been collecting miles for about two years and am looking to make my first big redemption. I'd like to fly from either SFO or NYC (very different, I know -- I'm going to base my plans around what flight I get) to Dublin in October. A few weeks later, I'd like to fly back from Barcelona.

Here's what I currently have:

Chase Ultimate Reward - 63K
US Air - 49K
Delta - 90K
AA - 66K
Iceland Air - 20K

I'm looking for some help: which program should I try to use?

Any tips or advice would be greatly appreciated.

Thanks!
Susan