Windows 7 doesn't have Telnet enabled by default, which I guess is fair enough since most people will never have to use it.  If like me you need to then you just need to click the following...

  1. Start
  2. Control Panel
  3. Programs And Features
  4. Turn Windows features on or off
  5. Tick Telnet Client
  6. Press OK

Hopefully this helps save someone 5 minutes some day!