Hi BGary, quite an adventure, huh? :-D
Ok, lets see, ok, you have the Scorched.LHA file on your 720k floppy. Copy it to your HD.
Take a look in your C: drawer, and there should be a program called LHA, which is what you use to unpack, if not, you have to download it from Aminet, or there should be a copy in that pile of disks you got. Copy it to the C: drawer.
Go into WB and look for the Shell program, which brings up a command line.
Bring up Scorched.LHA wherever you have it on your HD.
Type lha -x scorched.lha dh1:{name of the drawer you've got for this} and that should unpack the entire thing to the drawer.
If there was a problem in downloading the scorched file, it might be missing stuff.
Hope that works. Scorched is a pretty cool game.