Ok first off- did you format the disk before installing it cause if its got an old operating system on it and all the space is already claimed. Also are you trying to use an operating system disk when you start it and selecting boot from cd so you can format and re-partition it?
Honestly this thread makes it look like you took one drive out plugged the other in and just turned on the computer.... There is a lot more to it than that..
1-Swap drives
2-Insert operating system installation disk
3-Start PC
4-Press F12
5-Select Boot from CD
6-Format the hard drive
7-Allocate space for OS (should be automatic)
8-Install the operating system (OS)
9-Install hardware drivers
10- enjoy