I always joke with people that they need to take the plaid monorail from WDW to Universal. Fortunately (or unfortunately), no one has asked a Cast Member where the plaid monorail is.
To get from WDW to Universal without a car, there are several options. Here is a link to some good offsite transportation and the costs from Intercot.com:
http://www.intercot.com/infocentral/transportation/transoffsite.asp
A cab from the Swan at WDW to Universal costs about $40 each way for up to 5 people.
Someone else will have to tell you about Cornado Springs. I've only stayed onsite at WDW at the Swan/Dolphin and the All Stars.