Well, we can RAID 0 SATA drives with each drive using it's own SATA controller on the motherboard. Most motherboards have like 4 of them we can use with the IDE controllers reserved just for the DVD drive.
Probably not because getting two hard drives and having them in RAID 0 still treats it as one drive and not two separate drive. You're losing the other drive's capacity for storage if space is important to you. The performance is there, but won't "wow" you.