I then boot up in DOS and run ghost.

I assume you mean that the drive you're trying to ghost is on the secondary IDE controller and that your boot drive is something other than the one you're trying to ghost?

If that's the case, then that's correct: You can't hurt the drive if you don't write any data to it.

However if it's an NT (or 2k/xp) server that participates in a Domain, there are issues with the security database when you try to restore a ghosted image. The security account for an NT-based computer on a domain is updated about weekly. So about a week after you've made that ghost image of the drive, the image will contain a stale/invalid version of the security key and if you restore that image it won't participate in the domain any more. There are ways around this, but I won't get into the details unless you tell me that it's a Windows domain box that already has the trust relationship set up with the domain controller.