I see one outstanding Question:
SSH Tunnel using PuTTY no longer works after server change
Maybe I am a bit slower, but I read that a couple times and still can't figure out what you are trying to do exactly. I recommend often having what you are trying to do at the start of the question or in bold or something. For instance:
I have a Linux Server and a Windows Server, and a Windows Desktop. I am trying to connect to the Linux server from my Desktop via a tunnel I set up on the Windows server. I used to have this working, but on the Linux server, we moved the hard drive to a new physical server.
vs:
Prior to the move I was using PuTTY on a Windows box to tunnel web-traffic as a SOCKS proxy through the server using a Dynamic port set as 9870.
It is not that clear to me if you are using putty to set up the tunnel, or using putty to connect to the tunnel, or both. What is 'the server'?
So I recommend that your draw a picture, even with ascii art, or paint the picture with words. If you explain the situation very thoroughly, but concisely, you might get better support.
