TO GET ROCKET LAUNCHER:

BEAT THE GAME UNDER THREE HOURS, THEN YOU WILL GET TO
SAVE YOUR GAME IN THE HALL WHERE THE GAME STARTS. BY THE
WAY THE ROCKEY LAUNCHER HAS UNLIMITED SHOTS...OR YOU CAN
USE A GAME SHARK!(which I recommend highly)

TO GET NEW CLOTHES:

IF YOU SAVE THE GUY IN THE JAIL CELL(USE MO DISKS) YOU WILL
GET A KEY FOR A CLOSET BACK IN THE HOUSE, USE IT AND GET
NEW CLOTHES IT IS THE MAIN HALL ON THE LEFT HAND SIDE OF
THE HOUSE WHERE THE ZOMBIE IS LYING ON THE FLOOR AND
ATTACKS YOUR LEGS FROM THE GROUND IF YOU WALK PAST HIM
TO CLOSELY