I guess the first thing you should be worrying about is the order of your party. Put the strongest members at the top. Here we see what happens if you don't do this. The simplest thing is to follow the standard order of characters. Fighter goes on top, followed by Red Mage, Thief, Black Belt, White Mage, and Black Mage. You should really be concerned about who has the best defense and the most HP.
To switch order on the NES version just press select. (On the MSX version press F2.) You'll end up at this screen. Put the cursor on the character you want to move, hit the A button, move the cursor to where you want them to go, and hit A again. (On the MSX version you can substitute the space bar for A, and the ESC key for B.) There's no select button on the WSC so this function is in the regular menu. This also carried over to the PSX.
You'll see several houses that represent the town of Coneria. It doesn't matter which one you go into, they all go to the same place. There's also the castle of Coneria, which is a different place... to go to.