I have a Dell Dimension 8300, and I had a heck of a time getting SATA working. What I discovered was that I needed to include SATA support from within the SCSI section. For that, you have to be sure and answer yes to the question about including developmental and experimental features. Once you do that, there will be a Serial ATA section under SCSI. You'll need SCSI disk support as well. For whatever reason, SATA is implemented in the kernel in such a way that it looks like a SCSI device to Linux. So, your hard drive will become something like /dev/sda, with the partitions being /dev/sda1, /dev/sda2, etc. It's weird, but once I got it going, I found the performance to be incredible. BTW, my Dell uses an Intel SATA controller, and I would bet that this is the case on yours as well. So, go ahead and include Intel controller support under IDE as well, so you can access your CDROM drives, which still show up as regular IDE devices.
