In regards to your comments/inquiries, we have the following comments/suggestions:
1. "I am rebuilding my WHS VAIL..."
If yours is an Intel(R) desktop board, please, know Microsoft* WHS is not a validated operating system for the desktop platform. See the following URL:
2. "I am using an ICH10R chipset and I'm concerned about expansion."
I confirm RAID extension is supported; see the following URL:
3. "Should I be using Hardware or software RAID?"
I confirm the Intel(R) Rapid Storage Technology is both, hardware and software:
4. "Which RAID version on this chipset?"
The aforementioned Article CS-022304 shows the supported RAID features for the ICH controller in question.