I'm flying VIE -> WAW and then WAW -> ORD on LOT with only 40 minutes between arriving and departing. Does this sound remotely doable? Or should I do my best to get on an earlier flight out of VIE?

I have the opposite scenario on the way in as I'm looking at a 5 hour+ layover in Krakow. Can one kill this much time effectively in that airport between the shops and business lounge, or should I try to have lunch in town?

Any information would be most appreciated. Be kind to this first time poster!