You don't say how you are getting from the airport to the hotel. If it is by a towncar, many give a grocery stop along with way. If you are renting a car, I would just stop on the way to WDW. Take the south exit out of the airport to the 417. Get off the 417 at Orange Blossom Trail..there is an Albertsons and a Target Superstore you can shop at. Then just jump back on the 417 the rest of the way to Disney.
Or if you want to get to the hotel first, you best bet would be the Winn Dixie in Lake Buena Vista. Take Hotel Plaza Blvd to down to the lights in the Crossroads, take a left. Go past Palm Parkway, soon you will see Winn Dixie on your right hand side.
The only place I would advise you to stay away from is Goodings..it is much more expensive than the other stores.