We've never stayed at the Swan, but we stayed at WL when DD was 2, and she loved it there. We really liked being able to take the boat to MK. There is one that you can roll the stroller on, and the other you have to fold it. Most of the time, we were lucky enough to get the one we just rolled on. We liked the closeness to MK. At age 2, DDs favorite parks were by far MK and EPCOT. Being close to EPCOT with the Swan would be great too though. I think that the Swan's rooms are just slightly larger than WL, but since we have not stayed there, I'm not positive on that. I wouldn't split stay with a toddler- I think it is too much trouble to pack everything up to move to another hotel, but that's just me- some people are fine with it.
I will say that if you are used to adult only trips like we were, you will be surprised at how much a 2 year old slows things down. The biggest time suck will be the characters if she likes them- our DD was obsessed with them at WDW when she was 2 (still is at age 8). DH and I could spend a day in each park and feel like we had done everything we wanted pre-DD, but with DD at age 2- we needed at least 2 days at MK (really we would have liked more) and 1 day at EPCOT also turned out not to be enough. EPCOT definitely turned into a 2 day park once we had DD. The little like to stop and explore, and once they find something they like, doing it one time usually isn't enough for them. DD could have ridden the boat inside the Mexico pavillion in circles all day I think.
I will also give you another little warning- turns out those kids have opinions once they get there!


Maybe your DD will be fine with hanging out at the resort and not going to the parks some days and maybe she won't. Ours wouldn't stand for a non-park day at that age. Once she was awake, she would be standing at the door of the room with her stroller telling us to hurry up so she could get to a park.

Have a great trip! I think the 2 year old trip was my favorite with DD. Everything was new and amazing to her.