No, .NET framework it's not needed.
It's an installer thing, it checks your Windows version being either XP or Vista, to install some files in the proper locations. The XP version should be with at least SP1 applied, otherwise the installer will not run.
You can check your Windows version by choosing Start->Run and type "Winver" + ENTER
It must be build 2600sp1 at least. The complete minimum version number for XP SP1 is 5.01.2600sp1