What version of DirectX would be the best to learn with in Vista?

I am currently learning to write programs in C++, but I am ultimately going to have to learn to use an API, and I have decided to go with DirectX. However, my computer has Vista, and apparently the most recent version of DirectX is only compatible with Vista. Does this mean that programs written in DirectX 10 are incompatible with XP and before? Do older versions of DirectX work on Vista? How significantly does the knowledge a programmer needs to have differ between different DirectX versions?

What version of DirectX would be the best to learn with in Vista?
I wouild say DX10.1 since it is the newest going forward and you have Vista anyway. There is a greater installed base of DX9 but that will change over time.





Edit:Diya i clicked that link and saw the typical MS self high 5


shpeel but upon closer inspection i was like OMG Chuck Liddel is in Crysis... :D
Reply:http://www.gamesforwindows.com/en-US/Abo...
Reply:I write in BASIC so...


but that doesn't matter we are still prgmers





VISTA is uncompatible with many DirectX, such as Adobe Flashplayer wasn't out till so long ago.





VISTA is 64 bit so the DirectX cannot be 32bit... That's just it