ok, I lied. It's $18 more.
Newegg.com - Western Digital Caviar SE WD2500AAJS 250GB 7200 RPM 8MB Cache SATA 3.0Gb/s Hard Drive - Internal Hard Drives
As for the RAM, as long as both say DDR2 and the RAM is equal to or slower than the speed rated on the motherboard, you're golden. The 1066 speed is the MAXIMUM RAM speed supported. You can still run 667Mhz RAM without incident.
That HD looks good, and I have a WD in my current box so I'd lean toward one of these drives, but what is the difference between SATA and the UltraATA I selected with my build??