John's Seagull is one of my favorite places in Goa.
The food is great (do try the golden fried prawns). The beer is good. The music is good. You can play pool when you're bored. You can take a stroll on the beach. You can stay late if you know the owner (which I do) and he serves drinks on the house (to only those he knows, and only after the places has officially shut down).