You should be able to install Sonar Studio 8 on your shiny new computer. I would install both 32-bit and 64-bit versions.
If you upgrade from Studio 8 to X2 Studio,you wo;; get the option to download it - which is faster than getting the boxed set, and you can download it again, should you ever lose your original download files.
Studio 8 should work with either Windows 7 or Windows 8, HOWEVER, please note that any audio interface you are using needs to have drivers for either Windows 7 Windows 8 in order to function properly in whichever OS version you end up installing on the new computer. I recommend you do your homework on your audio interface, and if you are not currently using one, I HIGHLY recommend you look into purchasing one for your new computer.
Bob Bone