Depends on the day, the temperature, the chance of rain, how many people are with me, etc. I'm very flexible.
I've traveled through the parks with the following setups:
1. Sony T100 ultra compact and a plastic bag for waterproofing.
2. Sony DSLR-A300 and 18-250mm lens.
3. Sony T100 and Sony DSLR-A300 and 18-250mm lens.
4. Sony DSLR-A300 and 18-250mm lens plus 30mm F1.4 lens.
5. Sony DSLR-A300 and 18-250mm lens plus 50mm F1.7 lens.
6. Sony DSLR-A300 and 18-250mm lens plus 30mm F1.4 lens, 50mm F1.7 lens, flash, in medium Tenba bag
7. Sony DSLR-A300 and 18-250mm lens plus 30mm F1.4 lens, 50mm F1.7 lens, flash, in medium Tenba bag plus Slik tripod and remote shutter release
8. Sony DSLR-A300 and 18-250mm lens plus 30mm F1.4 lens, 50mm F1.7 lens, flash, extra battery, cleaning cloth, 5 filters, rain cover, remote shutter release, in Kata backpack
If I think it'll rain all day, I'll just bring the ultra-compact. If I just want to travel light, or am with friends where I won't be taking too much time setting up shots, I'll just bring the DSLR with one lens attached. If I think I'll be doing night shots, I'll bring a walkaround lens and a night lens plus tripod and a small bag. If I am travelling solo or with a photo taking friend, I'll bring the whole kit for maximum flexibility.
I also recently added a Tamron 10-24 UWA to my collection, so that will most definitely be included in my kit especially since I've never had a UWA at Disney - I'd imagine later this month I'll likely bring it every day and enjoy the new perspective it provides. I will likely still travel with the A300 and 18-250, and bring the Sigma 30 and the Tamron 10-24 in the Tenba bag for light travelling, or the whole Kata backpack with everything in it for serious photography days.
The only lens I don't bring to Disney is the huge Tamron 200-500mm - just too much lens to go hauling around the parks, and I don't want any trouble at security with that thing!