joker poker strategy question

In "joker poker" video poker where a pair of kings or Aces pay the same as a two pair....

Initial hand comes K K 2 2 7

Is it better to hold the pair of Kings only and try to improve to a three of a kind (3 chances to get 4 outs to make 3 of a kind)

Or is it better to hold the two pair and try to improve to a full house (1 chance to get 6 outs to make the boat)

Also...

Is there ever a time when it makes sense to discard a paying hand in search for a better hand, for instance...

10s Js Qs Ks Kh

keep the Kings or go for the potential straight, flush, royal flush

Thanks to anyone who can help!

I just learned this game recently. The wizard's strategy calculator and free play game helped a lot.

http://wizardofodds.com/games/video-poker/strategy/calculator/

http://wizardofodds.com/play/video-poker/

You can mark the circle that says "warnings" as training wheels. You can also use the statistics as a guide to see if you're ready to play live.