Raid 0/5 with Vista 32bit

[Edited]

Well, I installed my two new seagates in raid 0,einstalled vista on those, and it works pretty fast now (posting from my new (first) raid 0 setup), i have the maxtor left over. Since i have raid 0 with vista installed now, can i add the maxtor as a storage device as a single harddrive, and have vista read it? If not, should i redo it into raid 5 for redundancy, but i read that it will slow it down a bit, so i'm hoping i can just add the HD as an extra storage device. Thanks

Core 2 Duo E6850 processor
eVGA 8800gts 320mb videocard
Corsair pc6400 3Gb of ram
Abit IP35 PRO motherboard
2x (brand new) Seagate BARRACUDA 500gb Harddrives (now in raid 0, with vista 32bit)
1x Maxtor 500gb Harddrive (with vista installed on it, 32bit)