B.B.
My MIL likes the green bags...can't think of what they're called. I think she said she got them at Big Lots (but they're available other places, too). She said they help. I have bought some special tupperware style containers that are designed to keep fruits/veggies fresh longer, but I haven't really noticed a big difference.
In the winter time, I just buy less at a time and go to the store more often (twice a week for fresh foods vs one). I try not to buy things I know will go bad quickly this time of year (berries and grapes mostly). Bananas are still a must for my 14 mo/old, so I buy small bunches. That's really the only thing I've found to really work. I'm curious to hear what others say:)