Hi 710,
Sorry to hear you're only here for another 6 weeks. At least you've picked the best months to visit the town. Halle is "geil" in summer.
Ok, for cheap and good nosh near Krollwitz, try this place
Gosenschenke
Burgstraße 71
06114 Halle-Saale
Hmmm...looks good doesn't it. Well it's a bit nicer inside. It's student pub near Krollwitz. Across the bridge with the horse and cow on it. It used to do good cheap food. Hopefully still does.
Taking back bottles is easy. If the bottle has got "Pfandflasche" on it, take it back and hold out your hand for some dosh, if it hasn't simply throw bottle over shoulder and forget it. I can give you a real life demonstation of how this works if you like. You buy 4 bottles of quality beer, I'll come round and empty them for you. After that we take the empty bottles back to the supermarket/petrol station and collect the deposit. You then buy another 4 bottles and we keep repeating the process until you've got the hang of how it works.