Hi Laura,
Thanks for visiting the Disney Parks Moms Panel with your question! Deciding between these two resorts is a tough decision. Let me give you some thoughts that I hope will help.
The Royal Guest Rooms at
Disney's Port Orleans Resort - Riverside are lovely. I had a chance to tour them last year, and if your 4-year old daughter loves princesses, she will love these rooms. Overall, I also really like the lush setting at this resort. The theme at
The Villas at Disney's Wilderness Lodge is, in my opinion, a little subtler, especially for young children. The theme of Pacific Northwest National Parks may be a bit lost on little ones, and the rooms to tend to be a bit darker.
The Villas at Disney's Wilderness Lodge are geographically closer to Magic Kingdom than Disney's Port Orleans Resort- Riverside; however, The Villas at Disney's Wilderness Lodge are not on the monorail loop. You will still need to wait for either a boat or a bus to take you from The Villas at Disney's Wilderness Lodge to Magic Kingdom. The ride will be a bit longer from Disney's Port Orleans Resort - Riverside; however, I do not think that it is so much longer that it would be a deal breaker for me.
The final consideration for my family would be room layout and in-room amenities. A Deluxe Studio at The Villas at Disney's Wilderness Lodge feels a little bit bigger and has a kitchenette. That would be the deciding factor for us. Between the two resorts, we would stay at The Villas at Disney's Wilderness Lodge - though I totally understand why you might choose Disney's Port Orleans Resort - Riverside.
I hope that this helps you to make your decision, Laura! Have a great time planning your vacation, and please do not hesitate to ask if you have any further questions.