Join the club.
You can have a professional quality scanner that costs a fortune and takes minutes to scan each slide at 4000 dpi (it truly scans), or ones that are specialized digital cameras, i.e. they don't scan your slide but take a picture of it. Of this last kind, there are cheap ones that gives very poor quality, and more expensive ones that may give good quality if you know how to use them.
In all cases, you will probably have to fix / color correct each slide in some photo software. This takes from seconds to minutes.
Look for a scanner that has good reviews on specialized sites/forums. Also look for one that has
Digital ICE Clean-Up.
It is possible to get good results using a DSLR camera with a lens adapter, this takes high resolution pictures instantly, this is good if you can get the true colors, which depends a lot on the lighting.
Finally, you may want to select your best slides and send them to a professional service.