If you are driving down from Alabama, you most likely will be coming down I-75. There really aren't a lot of quick options for getting to WDW from I-75 except the Turnpike. You can take I-75 to I-4 and then go east on I-4, but it would easily add an extra couple hours and a few hundred miles to the trip. You could get off I-75 at the Hwy 27 exit near Ocala and drive down to Hwy 192, but that is a very long drive, and it goes through many towns on the way, adding an extra hour or two easily to the trip.
If you are really insistent on missing the Turnpike, it would make as much sense to continue across I-10 to I-95 and come in from the east than to continue down I-75 to I-4. Either way will add a lot of miles and time, but will get you there eventually.
The Turnpike is definitely the easiest and fastest way from I-75 to WDW. The new 429 toll road that goes south from the Turnpike makes getting into Disney a breeze.
