I use vuescan, scan on v700 at 2400dpi, use the post-scan reduction factor to bring the size around the 100mb territory and then adjust it back to reality in lightroom. I use the raw+dng output setting of vuescan.

Always scan in color and never let the scanning software do anything with curves or sharpening. Treat it like developing a neg - don't let the scanning software make it "look good."