There has been some progress Keef, No 1 can now access the files I want on No 2. No 1 is set up with Cisco VPN software so that I can access my work computers. I found, by a lucky break that this software had its own firewall, disabled that and problem solved.
However No 2 still cannot see No 1. I followed your Map the Network Drive process. It came up with the workgroup name, which the revealled the two computers, clicking on No 1 revealed the next level, ie Drive C, My Documents, etc. Clicking on My Documents brought up the files, however that is as far as I could get. I cannot open any of the files in My Documents. I then went to No 1 to confirm that My Documents was a shared folder.