Hi Laura,
Congrats on your first trip to the Walt Disney World Resorts!
Either option will work for you. Having a separate location to put your daughter down for a nap or bedtime is an advantage. Both options will have a refrigerator and microwave. The villa will have a stove, dishwasher and washer/dryer combination.
Consider:
Location-if you are concentrating on one park, pick a resort closest to this resort to save travel time such as the 
Polynesian if you are concentrating on Magic Kingdom. Or if your daughter needs to return for a midday break, the 
BoardWalk Inn or 
Yacht and 
Beach Club allows you access to two parks quickly.
Meals-if you only are going to have breakfast in the room, the one bedroom is fine in one of the family suites like 
Art of Animation and you will use the 
Disney Dining Plan. If you are going to cook all the meals, the villa will be better because of the stove. 
As for small grocery stores onsite,  
villas have a store onsite with limited selections. I order from the Garden Grocer and add items like suntan lotion and food with a greater variety. The delivery can be scheduled ahead of time and held until check in.
Wishing you a magical vacation!
Beth