Wait....what system are you using? XP or VX? I need to know, 'cause I'm not sure there is a Zelda system for VX. I might be wrong, but....
Also, if the sprites and tiles are already owned, then you can easily resize them using Paint (XP not Window7's Paint) or the newest GIMP, set the resizer to "None" and it'll work.
Each tileset will have to 32x32 and the characters will need to be placed in a template.