If you're at the WL, it doesn't make much difference. I agree with this:
If you are near the Downtown Disney area then instead of going to the supermarket opposite at The Crossroads shopping center in Lake Buena Vista, not even a 1 min drive down S Apopka Vineland Rd (turn left at the crossroads when exiting Disney) there is a Winn Dixie. For the things you listed it's definitely cheaper there than the supermarket at The Crossroads!
Just follow the signs to DTD, pass that up and continue down that road. When it curves to the right, it will take you down Hotel Plaza Blvd, which is curvy and has a bunch of hotels. When you get to the end of it, you'll want to turn left at the light. There is a Mickey sign there...you'll know you're leaving WDW property.
About a mile or two down the road, on the right, you'll find the grocery store. Although it would take me more than a minute, it isn't a ridiculously long drive. So if you're thinking, "It's been four minutes - we must have missed it!", don't worry. It's a decent one - well stocked with decent prices and not horribly crowded by tourists. If you want to stop at the counter, you can get one of their little discount cards. They offer them to out-of-town peeps. If you want.
Gooding's is closer, but is not always well stocked. I skipped too dings for that reason and not because I wasn't willing to pay their ridiculous prices. There is no point to going to a grocery store that is sometimes out of stuff, IMO. But if you want to go there, instead of turning left at that light, go straight. You'll quickly see it there, on the left.
Wal-Mart is probably as close, in the other direction...but it's horrid. I'm not one of those people who have a political issue with Wal-Mart, either. It's just a horrid one. Crowded, dirty, long lines. Yuck. The Winn Dixie is so much nicer and I don't think it'll take any longer to reach.