We have always used TIffany, and have NEVER been disapointed. The van will run you about $10.00 more R/T, but it is still worth it.
Make sure to let them know you need a grocery stop- And don't go to Goodings. Publix is a good choice, with nice selection, and cheaper prices. They won't have a prob. taking you there, but Goodings is closer to WDW, so its a little quicker for them. There is also a grocery, that you can fax your order to, and they will bag it up, and have it ready to go. I think it is ALbertson's, but I don't know the #. You could prob. search.