I have a KODAK Slide N Scan. It takes me 20 minutes to digitize 20 color slides. This includes the time it takes to remove the sides from their glassine sleeves, the time to blow off the dust from BOTH sides of the film, the time to center the slide in the device and capture it (after deciding on the best exposure) and the time to put all the slides back into their glassine sleeves. There is NO WAY I can scan 10 slides per minute!
There is a button on the top that says "RGB" if you hit that and then move the arrows up or down you can adjust the colors in your scan. I typically don't adjust that for slides, however if you are seeing colors different from your originals it is possible that was accidentally changed.