We have a Windows LAN environment, consisting of a Win 2003 server and various Windows Vista machines which authenticate against the Win 2003 server.
We want Windows users to login into these ubuntu boxes so that we can run some of our applications (say via ssh or rlogin - much similar to the way we login into our Amazon Linux EC2 instances). How do I enable this connectivity?
To login via ssh, you need to run sshd on your laptop. Usually done by running "service sshd start". MindTerm is an excellent ssh client that is java based and works well on Windows clients. Look here for more details.
If you want to run an X-Windows application, you will also want to setup a vncserver on you laptop and use something like TightVNC as the client on your Windows PCs.
