You didn't mention the format, which is critical. The most common is 35mm -- there are several options. For any other format -- 120, 620, APS, etc. -- you are probably going to be limited to commercial services. I'm also going to assume you're using a Windows computer.
I use two scanners. The Epson Perfection V300 is a standard, flat bed scanner with a film insert. It does a very good job at scanning, is reasonably fast, and comes with good software -- although most third party software works fine. I've had this for a year, so a newer model may be available. Also, the slide/film carrier feels flimsy and I don't think Epson sells replacements.
I also have a Pacific Image Prime-Film 3650U 35mm film/slide scanner. This does a better job, but scans one image at a time so it's slower. (It does a great job with 35mm slides.) I've had this scanner for 3 years or so, and I'd look for a newer model if I was in the market today.
No matter which route you take, scanning film/slides is time consuming, and will almost certainly require some editing in the computer to balance color, "remove" dust specks, etc. Don't assume you're going to be zipping through shoe boxes of old negatives in an evening.
Edited by Capn Easy, 13 September 2010 - 03:47 PM.