I am still confused why you keep mentioning winrar when you are having problems with adobe? one has nothing to do with the other usually....
make sure you have completley uninstalled the old adobe, reboot, then install the new one, reboot. make sure you can open a PDF, verify that file associations for PDF are set to open with Adobe.
I personally use FoxIT PDF reader, not as bloated, free,.. can get it on betanews.com