Option 2 is going to be very noisy, have a lot of interacting and probably pulsating case vibrations, plus be twice as susceptible to failure (RAID 0 system drive).
One simple option I like is:
- 7200 rpm internal system hard drive
- 5400 rpm WD Green Power media drive (I like the WD5000AACS because it is 2 platters; I used to own a 1 TB Green Power and felt it was significantly noisier; same might be true of 750)
(this combination of two different rpm internal hard drives doesn't pulsate acoustically like two 7200 rpm hard drives often seem too)
If you need another hard drive for time machine, an external one (connected to an airport extreme?) might work well and can be connected after you've got your Hackintosh up and running, and stable and updated to your liking.
Good Luck!
edit: if you are going to do any video editing, I again would recommend using an internal media storage drive. My dad's iMac uses an external enclosure for video editing, and iMovie sometimes just freezes for a milli-second here and there, and that isn't there with an internal drive. That WD Green Power drive had seek times of about 14 ms on my Asus P5W DH Deluxe, so I suspect that transient lag might not be there for this type of application.