RAID 1 Basic Question

I have newbie to moderate technical skills, so my apologies for what may be a really dumb question.

I have been asked to replace a failing 250GB hard drive in a SATA RAID1 array on a Dell XPS 410. The owner doesn't want to expand their storage, but they want to replace the failing drive.

Do I need to do anything unusual in the hard drive replacement other than power down, remove and replace, and boot up? On boot up, what options will I be looking at to make sure the new hard drive simply mirrors what is on the existing without overwriting it?

RAID Controller = Intel ICH8R/DO/DH
OS = Windows XP

Don't forget to ghost/backup the working drive before adding the new one.

By error you could mirror the empty one to the good one.

Brad