Is there anything on the Harddisk you want to keep? If not, you can go for the following:
Buy a set of Workbench-Disks on eBay or whoever still sells them, or find a set of Workbench 2.1 - images (Workbench Disk, Install, locale, Font, Extras) or have someone mail them to you.
Go here:
http://homepage.uibk.ac.at/homepage/c725/c72578/amiga/and
make sure you read the manual carefully.Then, with your WB1.3 Disk, transfer the Amiga-side-program and bring the Images to disks. Then you can make a fresh install of WB 2.1.
Have fun,
McTrinsic
