Stay at the Dolphin! Stay at the Dolphin!
It'll make you're trip so much easier. This is a beautiful resort and it's so convenient to everything. You can even walk to EPCOT and MGM if you want or take the boat. There's lots to do around the resort area with the Swan, BW, BC/YC within walking distance. The resort itself is wonderful and comfortable. Bus transportation to MK and DTD is also available. (and the S/D bus is the first bus at the line up outside MK when heading back)
I am not single but I take my almost 5 yr old dd to WDW every few months. (Dh just isn't into it like we are so he stays home and usually does a nice home improvement project and he does work of course). It makes for a nice mother and daughter mini vacation. And, I can do what I want, he he!
We drive from South Florida which takes about 3 hrs, not bad. The S/D and WL are our favorite resorts. I actually favor the S/D a little more because of their location, but the WL is a nice change.
I do have a car but when we stay at the S/D I don't use it much at all while we're there. When we stay at the WL I use it more because it is a little more isolated. However you do have boat access to MK, CR and FW.
My advice is to pick out the attractions and characters your dd wants to see most and then do those favorites first. You might want to take a rest after lunch time or later in the afternoon so you don't exhaust yourself and have a cranky dd. We only spend a few hrs in the parks mostly in the mornings then have lunch and head back to the resort for a nap. This way, the evening events are much more enjoyable.
You'll want to make a plan/itenerary that has some flexibility to it and depending on when you're going (if it's a busy time or not) you'll want to make PS for the character meals or even the regular sit down meals. You can always cancel them if you need to.
There are several character breakfasts-check out
http://wdwig.com/menu for the numerous selections! Have a great time!!