Whirlybird,
Driving from Dallas to Flordia would be a tough drive, but you could do it. You'd probably want a second person with you to trade off so you could drive nearly non-stop, but it would still take 18 to 22 hours depending on where in Flordia you were going, and that is driving non-stop. It is about 1,200 miles.
Check out
BestFares.com for cheap tickets. You can get it for about $200 round trip.
WF