My suggestion would be to use removepkg. YOu can find the full name of the package in /var/log/packages, and just do
where kpdf-2.5.666.tgz is the satanic package you wish to remove. See man removepkg for more details.
I don't know how cool Acrobat Reader is, but I will say that KPDF is pretty sweet, I certainly like it better than ACrobat Reader on Windows. they should coexist peacefully and you could just take the time to get to know KPDF.
Thanks for posting this message: now I know about removepkg!