I recently built and new system and have the following drives:
ATA HD, IDE HD, DVD-RW, DVD-ROM & CD-RW. I have the ATA drive connected to the SATA on the Motherboard, The DVD-RW as Primary Master and DVD-ROM as Primary Slave and the IDE HD as Secondary Master. I was thinking of trying to hook up the CDRW because it has a faster CDRW speed than my DVDRW. Will it work as a Secondary Slave to my second hard drive?

Should work with no problems. Just set the jumpers right.

I'm running my system with two ide HD's, a cdrw and a cdrom and no problems.

of course it will..just make sure you set it up with hard drive as primary + cdrw as slave and not the other way around

One thing you need to make sure of is that you have the BIOS set for Enhanced mode for the SATA/IDE configuration. The reason for this is that with an OS like Windows 2K or XP you can then use all four ATA ports along with the 2 SATA port for up to 6 drives.

If you use any other mode then you may not be able to see all 5 or 6 drives at once