Re: Hard Drive Questions.
I have a RAID 1 array for all the stuff/work that I really need and wouldn't want to loose should anything happen to one of the hard drives.
I then use another, that's equally partitioned, for the OS and a few app's.
Then I use the last, equally partitioned, to store downloads and other bits associated and the other part of this drive is my page file and all my music app's. Reason 3, CoolEdit Pro 2, etc.
Thats just an example of usage of HD space.
Use RAID 1 if you want to protect info you have on your computer, use RAID 0 if you want quicker read/writes to the this array. I.E. Video editing, Music editing, Game app's, etc.
Lenovo ThinkPad T410 - i7 620M - 8GB RAM - Crucial M4 120GB SSD - 250GB 2nd drive - Intel HD 3000 GPU - 1440x900 - Windows 7/8