well you had me confused and I thought you wanted to use blender 2.4x and had probs with a python addon

now your loading 2.6x .... and still got the error ??

is no need to install blender OR python !! just grab the zip unpack and run blender.exe

blender 2.5 plus probably wont run a 2.4x addon, I "think" blender 2.4x will have its own python in zip (unbrokenfighter will tell me if I'm wrong) so grab the zip of that version and try then

I don't "do" games but most will import a .obj just a lot more messing about without a "exporter/importer" addon