Recovery is only accessible via Fast Boot on the desire
To access Fast boot, firstly power off the device.
With device off press and hold the volume down key, keep this held down, and press the power button and release power button.
You are now in Fast boot. (Release the volume down key)
You will be presented with the Fast boot menu.
Use the volume up and down to move to different options in the menu.
Select the Recovery option using the power button to select.
You will then be presented with a screen similar to the G1/G2 handsets (picture of phone with warning triangle)
Press volume up and power at same time to get recovery options.
You will then be presented with the recovery menu.
Again use the volume up and down to change options and power key to select