When automating your Lite-Touch environment, you should first consider the usage of your task sequences. There are 4 task sequence usage scenarios in MDT 2010, they are the new computer scenario, the refresh computer scenario, the replace computer scenario and the upgrade computer scenario.
I will explain deployment scenarios in detail in a future article but for now to bypass the pane displayed in the deployment wizard use this line in your custom settings.ini:
Then to select your deployment type. For a new computer scenario use this example:
The other options available are REFRESH REPLACE and UPGRADE. Again I will explain deployment scenarios fully in a future article.