My husband and I stayed at Saratoga Springs in January 2008 with our toddler and 5 month old. We chose Saratoga Springs because it was Disney's newest resort and we figured it would have the least wear and tear. The hotel was clean, comfortable and nicely furnished. We rented a 1 bedroom villa, which was plenty of room for the four of us and allowed us all to sleep in different areas of the villa. (Important for us so our children would not wake each other up and we would not have to go to bed with them at 7:30 pm!)
I would say the room is equal to a 3 star hotel room, on par with a Marriot. We had a pool right outside our room which was quiet and convienent and the larger, more crowded pool was a 10 minute walk away. We were able to walk to Downtown Disney from our room, also about a 10 minute walk with two kids in a stroller.
Disney provided a pack n' play for the baby and we had them deliver a crib to our villa for our toddler. Both worked out well.
Since our villa had a kitchen, we bought some groceries at the Artist's Pallette, which is the quick service restaurant near the main pool. They have a small grocery section and carry a fairly decent range of items including eggs, waffles, milk, juice, cereal, bread, some canned goods, paper plates, baby food, aluminum foil, beer and wine, etc. The prices were a little bit higher than you would find at home but not too bad. One note for parents: I didn't see diapers but was told they only sell Huggies in Disney. (for Pampers users out there) We brought them with us but a good tip I got was to order some online (maybe from Amazon?) and have them shipped directly to the resort. The resort will hold them for you until you arrive.
We took the bus twice a day to the parks. The bus stop was just outside our room and the wait was fairly short wait as was the ride. We were able to fold up our double stroller and carry it on to the bus with us to the parks.
We thought we would be spending more evenings having dinner in Downtown Disney than we did. It ended up that we had dinner most nights in Epcot. In hindsight, it would have chosen a villa at the Boardwalk or Beach Club, which are both in walking distance to Epcot. I can't stress this enough - Make sure you make dinner reservations before you leave for your trip. At least for the first night. By the time we checked in, got settled and got our bearings, we quickly realized there was at least an hour wait for most restaurants. We were hungry and tired from travelling all day and the hour wait with two kids was just not an option!
On last unrelated note: Wherever you stay, try to go check out The Wilderness Lodge. It is a really fun property, the lobby is especially cool and I think they also have villas.