> tells me home sharing is not turned on, but it is, it is always on.
No, it is not always on. The fact you are being told it is not on is kind of a hint here that it is NOT always on. There are lots of things can can block it or shut it off. For starters is the computer iTunes is on active ( not asleep ) and is iTunes running on it?
>i can get youtube from my computer
No you don't. Neither your computer nor home sharing is invovled when watching YouTube content.
>i can get netflix, etc but not the movies
Because Netflix is not using your computer or Home Sharing.
>sometimes when i do get it they stop and tell me turn on home sharing
Because the Home Sharing service connection is being lost. Which again it is telling you. As mentioned that can be caused by a lot of things.
>i have put an extension plug into the room next to the apple that brings the net closer
You what!?!? What exactly are you doing? This makes no sense. Hows does plugging in a electircal entention cord "bring the net closer"