If you are using the homegroup, the default is just to share the public library files.
If you really want to share everything, right click on the drive to share, select properties, sharing tab, advanced sharing, and click the share this folder box. Then go to the security tab in the drive properties, edit, select add and type in "Everyone" into the add object names box. Then everyone (all computers, users) on the local network will have access to everything on the shared drive -- files, programs, everything.