Can I use Contribute 6.5 or any other ver for Windows 8 OS?

If you look thru the Contribute forum you might find some helpful info - there is one where someone had some trouble with that getting Contribute CS4 working on Windows 8 but resolved the problem.  You could even post your question there to see if a direct answer is provided.

http://forums.adobe.com/community/contribute?view=discussions

Another thing you might do is download and install the trial and see if it works without issue for you.  That should be done anyways to help avoid buying it before finding out it won't work for you.