Configure SATA HDD on GA-P35-DS3R

I need some help figuring out how to configure my drives- I've never had a SATA setup before. I have a Gigabyte GA-P35-DS3R motherboard, two 250Gb Seagate SATA drives and a DVD burner.

Now, there are 8 SATA slots on the mobo- two are purple and I think are for a RAID setup, which I am not doing. So I assume I should just use the orange slots. Should I install the boot drive into any one of these in particular? Should the boot drive be channel 0 master?

Also, should I enable AHCI for these drives, even though I'm not using a RAID setup? The bios gives three options: Disabled (configures SATA controllers to PATA mode), RAID, and AHCI.

I've tried a couple different ways, and each time when I try to install Vista, I get a warning that the BIOS controller may not be setup to recognize the drive as a boot device.

Any help would be appreciated. Thanks.

The Orange are the ICH9 ports and the other two are powered by some 3rd party controller (sis?).

I didn't have any issues installing Vista business ed., I'll check my settings and post back.