If you would like to block the delivery/installation of IE7 to your windows machine, an addition to the registry will do the trick.
the following key/value needs to be present to block the delivery
Registry key: HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Internet Explorer\\Setup\\7.0
Key value name: DoNotAllowIE70
Key value: 1
You can add this with a .reg file by saving the following as a text file and giving it a .reg extension and then double clicking it. (It needs to be four lines as shown with spacing as shown)
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Internet Explorer\\Setup]
[HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Internet Explorer\\Setup\\7.0]
"DoNotAllowIE70"=dword:00000001