Hmm, this is one of the more unusual questions that I have received lately...
how do you setup asp.net 2 along side with asp.net 1.1 in Windows 2003/IIS6? do i need sdk or redistributable package?
The Redistributable package allows you to run .Net applications. The SDK just contains additional tools (like ILDASM, SN), samples, documentation, etc necessary for a developer to fully develop with .Net.
Since it sounds like you just want to run different versions of ASP.Net side by side, you just need to:
ASP.Net 2.0 will automatically be set up as the default.
Since you cannot load multiple versions of the CLR into the same process, you cannot run applications of different ASP.Net versions in the same Application Pool. For IIS6 in Worker Process Isolation Mode, this means that you must:
ASPNET_REGIIS.EXE of .Net Framework 2.0 has several options that you want to explore concerning versioning of .Net applications and appropriate configuration of IIS Scriptmaps. You probably want to head to http://www.asp.net for more community information, or read this topic on MSDN