interesting that you say that, what browser are you using?
I'm using Firefox Philly and have had Flash 10 on here for some time now and haven't had any problems uploading anything. The only thing I can't do is update images on my personal site...for that you need Flash 9 and here is an archive for all previous Flash players.
http://kb.adobe.com/selfservice/viewContent.do?externalId=tn_14266
And here's the Flash uninstaller to use before chaging Flash Players.
http://www.softwarepatch.com/software/flash-uninstaller-program.html