I bet you are Pumped Joel!
Make sure you have your Good Sam or AAA in place and a few basic tools if you are a handy kinda guy.
The radio, should be a minimal drain, so dont wory about it until you get home, and can get a Multimeter on the battery post and lead and get a reading on what the drain really is.
The generator could be a few things.
The gas tank being 1/4 full or less... The gas dip tube for the Genset is shorter, so you dont run the tank too dry to drive to the gas station.. I confirmed this myself recently.
Other ideas: Gummed carb or blocked filter, bad fuel pump, low oil level.
If the genset, and indeed the motorhome itself has not run much recently, i would toss a couple of cans of Seafoam in before the drive... about $8 a piece in Walmart, and I have personally seen how good that cleans carbs!
The dash air should be easy to fix, but unless its been converted, it will be R12... and stick to that as the R134a convertion never run as cold in my experience..