First, that is not sql error that you should look at the first place even though that error might cause the failure. Go to windows directory and search for sqlstp.log and take a look at that and find why the sql server installation failed and then find from event log that is related to that error.
Let me or other people know if you find anything else.
BTW, you might have bad media.. I've heard that error not just from SQL installation also from IIS and any other installation from Windows XP/2003 Server box.