"Read Only"

I'm having trouble with files and folders on my second hard drive. These
files existed before installing vista. It seems that Vista has marked all
files and folders as read only and I can't change that. (un-checking it has
no effect, just changes back to read only after closing and re-opening) Is
this a bug, or something microsoft did as a safeguard? Is there anyway I can
fix this or a workaround so I can modify files? (eg. rotate pictures,
resize, replace existing files with modified ones, etc.)
I've even tried using Irfanview to modify pictures and save them, but it
won't let me replace existing with modified.