Could be a bad burn... Did you run the media-check? That will tell you if the CDs are good or not.
If one is bad, you should run an MD5 check on the ISO before you re-burn it. You can get a Windows version of the program at... << www.md5summer.com
>> This will tell you if the ISO is good or not. If it's not, there's no use burning a new CD until you get a correct download.
The RedHat icons package is prob'ly not something you can skip. Unless you install without X.