from my experience walmart camping gear falls apart realy quickly and isnt worth the money, the only thing i can think of worth buying from walmart for camping would be the grease pots they sell. and im not even sure if they sell them anymore, but they are a great addition to yer cookset if you can find one while yer there.
ide recommend getting a new sleeping bag/sack set up. you get what you pay for, but if yer lucky you can snag a nice mummy sack with a decent stuff sack for 40 or 50 bucks from yahoo or amazon. i found mine at an army navy store (surprising for how light and small it is) for not to expensive, its got a realy nice temp rating, it weighs about 4 pounds and is only a little bigger then a football when its in the sack.