Your best bet, I think, is probably the Amtrak service between Kissimmee and Tampa, which takes just over 1.5 hours one-way. This will drop you in the city, so you don't have to worry too much about local transport once you arrive. A bit closer is Winter Haven, which is an inland town with a few mellow attractions like an aviation museum and a striking tower atop 295-foot Iron Mountain. You'll probably need to taxi-hop once you arrive here, though. You could also hit the beach at Daytona Beach via Amtrak, but it's a bit of a schlep as you'll need to do a bus transfer (one-hour ride) from the actual station at Deland.