Removing ALL drivers will damage windows and make your life horrible!
Your are better off selectively removing the drivers.
Boot from Windows 7 DVD
Select Repair and command prompt
Lists all drivers
Dism /Image:C:\test\offline /Get-Drivers
feed the list one at a time into the remove command below. It is only necessary to mount once, not once per driver.
Dism /Mount-Image /ImageFile:C:\test\images\install.wim /Name:"Windows 7 HomeBasic" /MountDir:C:\test\offline
Remove a specific driver from the image. Multiple drivers can be removed on one command line. For example, type:
Dism /Image:C:\test\offline /Remove-Driver /Driver:OEM1.inf /Driver:OEM2.inf
Removing a boot-critical driver package can make the offline Windows image unbootable
Adding drivers also has a command
Dism /Image:C:\test\offline /Add-Driver /Driver:C:\drivers\mydriver.inf /ForceUnsigned
Dism /Image:C:\test\offline /Add-Driver /Driver:c:\drivers /Recurse