sata is a faster interface, normally what is used is IDE 133
ide 133 transfers at 133 MB/s while sata 150 transfers at 150 MB/s
and i forget what raid stands for but it can be used for several different ways
the one you will prolly ever want to use if RAID 0, which will take any drives on the raid array and make them appear as oen drive(referring to hard drives)
there are two other big array types
RAID 1 reserves half of the total hard drive space to make an exact mirror of the other half
and lastly is RAID 5, which i wouldnt suggest u use unless u got at least 6 har ddrives
RAID 5 will spread out backup data across all the drives, which is considered the most secure way to protect the data
most built in raid drivers onyl support 0, 1 or 0+1, so ignore the 5
(and yes i know there are more types, but they arent worth mentioning)