In order to change the homepage of the Google Chrome browser, installed on a win7 pc, you can change the homepage, e.g. via login script. (see e.g. http://www.chromium.org/user-experience/user-data-directory for chrome info)
Of course you can load adm files in your domain controller, but it can be done scripted.
powershell -command "(Get-Content 'C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Preferences') | ForEach-Object { $_ -replace 'some.url.tld', 'someother.url.tld' } | Set-Content 'C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Preferences'"
Hope this helps you.
Edit: For your info, the above command changes all occurances of ‘some.url.tld’, beware that any other setting with this value will also be adjusted. cheers.