I don't speak any Polish, but there are definitely some similarities to Russian which I know nearly fluently so I'd probably be able to pick it up after a year or two.
Am I correct in thinking that that means you will want to do one of the English-language programs? If so, save your money: those are very much second-tier programs and run only to make money for the university. As 'golden goose' courses, it's quite hard to flunk out, which further devalues the courses.
Both universities have worldwide recognition
As far as I'm aware, neither make the top 300 in any of the major rankings, and that ranking would be for their superior Polish-language programs.
As a tourist, I'd choose Krakow over Warsaw.
You'd need to pay me to go to Krakow at the weekend: way too many drunked morons from the British Isles there now at the weekends.