If you ever do a Visual Studio .NET 2005 unattended install, you’ll notice that the installation reboots the machine several times and won’t continue until you log back in – defeating in part the purpose of the UNATTENDED install.

Well, this page over at Aaron Stebner's WebLog has some instructions that can help you make your installation REALLY unattended. It requires two things: first, remove some pre-requisites that end up on the vs_2005.ini files regardless of what you do (instructions here), and second, create a batch file that installs both the prerequisites and VS.NET. This is the code in the batch file for the unattended install on x64 boxes (run it from the VS dir):

wcu\msi31\WindowsInstaller-KB893803-v2-x86.exe /quiet /norestart
wcu\dotNetFramework\x64\netfx64.exe /q:a /c:"install.exe /q"
wcu\DExplore\DExplore.exe /q:a /c:"install.exe /q"
setup\setup.exe /unattendfile vs_2005.ini

For other machines, you may need to change the architecture of the .NET framework for the correct one (x86/x64). I made that batch file for an unattended install a few months ago at a 64–bit event where I had to install Visual Studio in around 30 machines, and it worked like a charm. YMMV