Microsoft has released some useful guides to help you during the installation of Windows 7.
Manual Installation of Windows 7 - You can upgrade to Windows 7 by installing a clean copy of the operating system without keeping applications, and you can easily transfer your files and settings from the previous Windows version. You can optionally upgrade computers running Windows Vista with Service Pack 1 to Windows 7 while keeping your applications.
Upgrading to Windows 7 with a Standard Image - Use this method to upgrade to Windows 7 if your business has 100 – 200 client computers with a small network, possibly in multiple locations.
Automated Installation To Upgrade Windows 7 - This step-by-step guide describes how to use the Microsoft Deployment Toolkit 2010 to automate Windows 7 installation from the image that Microsoft ships on retail or volume license media, including automatically installing applications, device drivers, and updates after installation.
Upgrading to Windows 7- (for small and medium businesses) This document helps people who are responsible for upgrading to Windows 7 choose the best deployment method for their environments.
Automated Installation of Windows 7 - Use this method to install Windows 7 if your business has 200 – 500 client computers, at least one location with more than 25 users, and managed networks based on Windows Server, possibly in multiple locations.