For dev work I'll probably just buy one of the languages (ie C#, or VB) since I don't need the entire studio and it's ALOT cheaper...I just have to be able to do a little .NET work for some clients on occasion.
Make sure to install IIS first, before you install the dotnet framework on the first time around. After that, if you ever uninstall the IIS and reinstall you must run a utility called dotnetfx.exe after you reinstall the IIS. The utility comes with the dotnet framework download.
This modifies the IIS metabase to know about .NET. If you install dotnetfx, that actually just reinstalls the .NET framework, which is unnecessary. The v1.1.4322 in the path above should be replaced by the highest version number you have installed of the framework.
aspnet_regiis can be run at any time to fix the IIS metabase to know about .NET. There is no harm in running it multiple times.