Historic Stare Miasto (the Old Town center specifically, not the entire district) is one of 2 epicenters of the Krakow food and entertainment scene, with an abundance of cafes, restaurants, bagel stands, basement bars and clubs strewn about the streets surrounding the Main Square. In fact, it's been said that there are over 300 drinking venues packed into this neighborhood alone, but few are those who can claim to have stayed sober long enough to count them all. But we digress.
Because of the constant influx of tourists, you can expect prices to be high, but thankfully they're still not terrible by international standards. Yes you'll be surrounded by other foreigners and the all-too-common stag/hen party-goers but, if you're looking for a one-stop shop for a night of dining, drinking and dancing in one of UNESCO's first World Heritage Sites, it's a can't miss.