Remote Desktop Windows To Linux

There are probably a ton of ways to do this, but here is one.:)
Use X11VNC on Linux and a standalone TightVNC client to connect to the Linux machine from Windows.

1.  Install X11VNC on Linux (Ubuntu)
   sudo apt-get install x11vnc
2. Run the VNC server on Linux
   x11vnc
   or
   x11vnc -forever
   to keep listening for new connections after the first client has disconnected.
   WARNING: X11VNC runs without password as default, you should set a password if you intend to let the server run in the background or for longer periods.
3. Download standalone (or installer if you have the rights to install) of TightVNC:
   Latest version, installer only:
   http://www.tightvnc.com/download.php
   Old version, standalone:
   http://www.tightvnc.com/download-old.php
   http://www.tightvnc.com/download/1.3.10/tightvnc-1.3.10_x86_viewer.zip
4. Connect to your Linux machine (use ifconfig to get IP-address) using the TightVNC viewer.

Consider adding x11vnc-forever to your /etc/rc.local and make it executable to start a VNC server when your computer boots.