Hold it, hold it. Before you switch, I hope you read this.
The USB drive problem can be solved quite easily by editing /etc/fstab and adding an entry to allow a USB based drive. When you insert it, all you have to do is mount it.
As for the printer, have you checked
http://linuxprinting.org? You can update to a newer version of CUPS without getting an entirely new OS. Updating to FC4, which IMHO is far inferior, is uncecessary.