To 1, that's not what the

TV is for- it's not supposed to be thought of like an external hard drive, just like your iPod is not external storage for your iTunes music. The

TV is supposed to be seen more like an iPod for your TV. Frankly, I wouldn't do what you are asking if I was you.
But, it is done and there are apparently ways to pull the movies back to the computer if you need them later. However, note many threads that regularly appear in which someone accidentily synchs, wipes out the movies that were stored only on the

TV and then is angry because they can't get them back.
There are also hacks that let you hook up an external hard drive to the USB port on the

TV and use it more along the lines of what you seek.
BUT, best option would be to buy an external drive for that laptop, store your movies there, and then sync with the

TV as it is intended, OR stream to the

TV. Big storage is dirt cheap. If your laptop is getting full, that's the BEST way to go.