I would definitely agree with The Don on this one... Running and Rolling are great ways to build your wind. I would also include swimming and dancing. Yes, dancing. Swimming would greatly teach your body how to utilize the available oxygen, as (if you're doing it right) you won't be constantly breathing or sucking wind with every stroke. Dancing is more of a "covert" workout, as it is very demanding, but since most don't treat it as exercise (a leisurely act rather) you end up working out a lot without thinking about it.
On the subject of mats, 8' X 8' should be the smallest minimum size you'll be look for to work on. From their, you're probably looking at $400 starting for anything that size. I believe there are a few deal going on ebay for 10' X 10' sections for around that much (granted you're going to end up paying at least $60 on shipping on top of that), but that's really not too bad of a deal.
It doesn't matter if you agree or disagree
... As long as I don't bore you and I spark a moment of thought, my goal is achieved
Queng leon queng tigre ecu tacacut, queca pa? - Pampangan Mandarigma Motto