1. NO - you need a computer
2. See above
3. Yeah, there are lots of FM receivers (even simple USB) for comptuers figure $100.
If you just have the screen, what you want to do is go get a DVD player. You might be able to find a $30 home DVD player** (I got two at best buy for $19 each) and a $20 power inverter (if you don't have one - mine I built into the truck's rear console)

Plug the RCA video out into the video input of your screen. The remote is how you are going to access the menu.
** I don't know how well a home unit will play in the car - if you hit bumps will it skip? Maybe. You will also have to start over each time you power off. So if you stop for gas, turn the inverter off, you better remember where the movie was at, cause you are going to be doing some FF action.