Conditional Install of .net 3.0 or .net 2.0

[GrantArgy]

My setup has three install options (Client Only, Standalone, and Application Server). If Application Server is selected I want to install .net 3.0 else .net 2.0.
If I tick as application runtime it installs as prereq which is not what I want.
I am going to try to write it conditionally using some of the generated script for both versions of .net, but any suggestions would be appreciated. Also if I run an exe and wait for it to complete can I still grab return values to continue and if it forces a reboot will the setup return to the correct position?

[MichaelNesmith]

You can essentially move the code around to any part of the setup script that you want. So you could call the part that installs the runtime from the main installation body, equally as well as calling from the start of the setup program. The default script simply uses a prereqs block because users should know that they are receiving system wide updates and agree to those before moving on to your application's actual installation.