http://www.disboards.com/showthread.php?t=595713
That is the FAQs for this board and has links to pictures of ride vehicles and other info.
http://disneyworld.disney.go.com/plain-text/
That is the official online version of the guide for disabled guests at WDW but may not be updated recently or the info may not be correct. CMs and their bosses rule the parks not the people online so use that as a guide only and check with sites like this one for current info.
http://disboards.com/showthread.php?t=818020
Talkinghands and others discuss rides and accessibility.
http://photopost.wdwinfo.com/showgallery.php/ppuser/2590/cat/500
Sue's photos of ride vehicles
http://www.allearsnet.com/tp/gal_ride.htm
Another ride vehicle picture.
What rides are for people that are in a wheelchair? Chuck got some but there are more. All shows including ones like Hall of Presidents and the Tiki Room are
ECV and wheelchair accessible.
These can hold a wheelchair.
Magic Kingdom
Jungle Cruise (ECV and Wheelchair)
Buzz Lightyear's Space Ranger Spin
"it's a small world"
Magic Carpets of Aladdin
The Many Adventures of Winnie the Pooh
Liberty Square Riverboat (ECV and Wheelchair)
Tom Sawyer Island
Walt Disney World Railroad (Wheelchair and no ECV but they do sometimes let on small
ECVs)
Animal Kingdom
Rafiki's Planet Watch (ECVs are allowed everywhere but on small booth and the affection area)
Wildlife Express Train (ECV and Wheelchair)
Affection Section
Kilimanjaro Safaris
TriceraTop Spin
Hollywood Studios
Studio Backlot Tour (ECV and Wheelchair)
The Great Movie Ride
Toy Story Midway Mania!
EPCOT
Ellen's Energy Adventure
Journey Into Imagination With Figment (ECV and Wheelchair)
The Seas with Nemo and Friends Attraction (ECV? and Wheelchair)
El Río del Tiempo
I think the guidebook is wrong about Nemo being ECV accesible and a transfer is needed but never rode it.
The riverboat and rafts depend on the water level. At DLR I was the last ECV allowed on board as the boat was too low for them to load. At DLR the raft was a couple inches high and I did not need a ramp but boy was it high on the other side and no way I could jump the
scooter off the ramp. So you may have to wait to load on those two.
I hope that list helps.