PBase

When I scan for 14-bit NEF files, then convert them to jpegs (8 bit) for the web, do I get different or "better" color than if I scanned at 8 bit? Or will the result be exactly the same as if I scanned jpegs at 8-bit?

Depends...
If it is a straight operation like you said, they will be the same (or so close you won't be able to tell).
The differences happen when you start manipulating, if you adjust contrast/brightness/hue/saturation/ etc. Then the extra info can come in handy as the extra bits are being moved into the translated space.
If you resize sometimes the extra info is used in the interpolation.

Of course you can even do limited hdr with the single picture....