NEEDING SOME ADVICE KINDA STUCK

lol @ being worried about people stealing your ideas based on abstract descriptions of the plot. You could write out an entire script and post it here and beg people to use it and they still wouldn't. In fact something like that happens every few weeks. People are always trying to get other people to make their games for them. But we all have our own ideas we are busy trying to make. Everybody wants to be the ideas guy and no one wants to do the work.

But yeah I guess it sounds like step 1 is to learn how teleport events work. You want to put an event in the doorway, with no graphic. It should be triggered on hero touch, so that it happens when the hero steps on it. It doesn't need any conditions - you want it to always happen every time the player steps on it, presumably.

On the right side of the event screen is where event commands go. This event only needs one event command because it only does one thing. And that thing is to teleport the hero outside. Double-click in the empty list of commands to create a command for the event to do. The command you want is called "Transfer Player". When you choose it, it'll ask you to pick a destination. The destination can be on the same map or a different map. Since the door sends the player outside, it's going to be a different map (the outdoor map). Pick the outdoor map and pick the spot on it where you want the hero to end up.

Now you've got a working door. The door outside the house should lead to the inside using the same method.

I think Merte just posted a series of videos on getting started in Ace. http://rpgmaker.net/tutorials/

This also seems like a good starting point:
http://www.scribd.com/doc/88474618/Beginner-s-Guide-to-RPG-Maker-VX-Ace#download

Good luck! (btw I'm 32 and I still haven't really learned Ace)

EDIT:
apparently that document is behind a paywall now. lame.