What symphonix posted should work, let us know if it doesn't.
The problem is not privileges on the drive itself, but on those specific files. Each file on your hard drive has an associated owner and permissions. So you may have read and write permissions for everything on the drive except those two files. (That's not really how it is, you don't have permissions to modify a bunch of files, but that's the way it's supposed to be)
I think I may have already pointed you towards the
Unix thread, which discusses permissions a little more thoroughly. If not, slap me around and call me a silly tortoise.
Oh, one other thing to understand: Mac OS X is unlike any other Mac that came before it. Since it's based on Unix, it gets a lot from its Unix parents. One of those things are permissions. Unix was developed to be a multi-user, multi-processing operating system, connected to a network. When they looked at what is necessary for a networking operating system, they noted that they only want outside users to be able to do certain things. For example, they don't want anyone without privileges to delete system files, or change how things work, or make a general mess of things. But they still want to be able to change these things themselves, so the idea of multiple levels of users came into being. One of the many strengths of Unix is the security it offers. So when you log in using your normal account, you are running in a slightly restricted mode. There are things you can't do, files you can't delete, et cetera. But your account, since it is set up to be able to administrate your computer, can temporarily be bumped up to unlimited power. That account is called root. If you are root you can do anything, including royally messing up your system if you so desire.
The problem with running as root is that if you delete the wrong files, you could easily destroy your operating system, forcing you to re-install.
Okay! Enough rambling from the tortoise!
