Not sure what to tell you. It installed for me at first try.
Max
Version 3.10 will work fine. Just go to the download section of Logitech web site, select your mouse model, then for OS chose windows 2000 and it will let you download version 3.10.
Max
Windows 2k8, like Vista, comes with DX10, so there is no need to install DX9 on top of it. Any DX9 will work just fine with DX10.
Max