Frankly, you might be better off just hiring the job out. Scanning slides (and negatives) isn't as simple as simply running them through the scanner like a Xerox machine - you have to worry about color/contrast levels, size, scratches, etc, etc. Plus, to do it right, you need expensive equpiment and a LOT of time.
If you enjoy it as a hobby, that's one thing, but otherwise you'll find it tedius and dull I think. Plus, slides and negatives contain a lot of information - so the raw filesizes will be huge. Don't skimp on that in order to fit them on a DVD for family -- keep the huge images and scale them down for the relatives.
I have this device and it works great -- I actually paid LESS than this about 2-3 years ago, so the thing holds its value extremely well apparently:
http://www.amazon.com/Nikon-Super-CoolScan...6998&sr=8-1
You'd need to buy a slide adapter too.
I'd definitely recommend ICE, especially if the slides are old and scratched. It will remove the scratches from the slide automatically.