Congratulations on your new adventure. A few quick things to know.
Have them show you the procedure on how to winterize and dewinterize your RV. Know where the water heater bypass valves are and know where the water pump is located. Understand how to set the thermostat to operate the furnace and AC. Have them show you how you set up a tv for OTA television. Get the form to get a 2nd year warranty from FR, usually $150, don't buy their 5 year 2nd party warranty. New TT's come with a year of Coachnet road side service. Lots of thing you will find you need to go camping, extra fresh water hose, extra sewer hose, 50' coax for tv hookup to cable service. As for tv size take a tape measure along and find out for yourself if there is room. There should be a sticker on the wall for where you can mount a tv.
If you see something that needs to be repaired or fixed do not leave their business until it is done, once you leave they won't remember who you are. If they say go ahead and take it home and bring it back and we will fix everything don't believe it, once they have your money they are in no hurry to fix anything.
Those are just a few of the high points, you should have been asking these questions a couple weeks ago. A little late for a crash PDI course.
Go here and join the fun:
http://www.forestriverfrog.com