Computer:
For any computer builds, I would suggest spending a little more and getting a well-known and more reliable brand of motherboard (Asus, Gigabyte, Abit, MSI, to name a few).

I don't know what is specifically wrong with the motherboard. Returning it for a different brand would be the best solution, but it may cost extra for restocking fees and such.

Webpage:
You should consider using a CMS. It bascially is a complete website backend and interface with users and editable content and pages.

Check this out:
http://www.opensourcecms.com/
(portals(CMS) on the left menu)
You can try out a number of free open source Content Management Systems until you find one you want for your site. I personally suggest trying Drupal or Mambo.

Hope this helps.