File Permissions on Copied Files

We recently had to rebuild our SBS 2003 server, but we had saved the old
disks with all our data on them. We copied the directory containing all our
data (spreadsheets, letters, etc.) from the old disk to the new server and
then shared the base directory. I need all the people on the network to be
able to read and write to all the subfolders of the base, shared directory.
But, all the sharing and permissions tabs are grayed out on the subfolders,
as is the "inherit permissions from parent" checkbox. How do I change
permissions? Right now, no one has write access.