Hey Andy -
I have the same scanner. The picture format itself is not really a function of the scanner, rather the scanner software that you use.

The drivers that come with the scanner will allow you to scan a picture and save it as a BMP (as you noticed through the wizard they give you). More than likely you will want to get some different software to help you scan and manipulate the image. I suggest you take a look at some different packages such as Paint Shop Pro (free trial available from their website). You can save the picture in a number of different formats with different color depths. JPG or GIF are probably best for use on the web. Other formats are better for publications or screen use.

As long as the software can use a TWAIN compliant scanner, then you can use it with your scanner. I am using Adobe Photoshop 6. Its a very expensive, feature-rich program that is WAY too much for scanning chips. But once you get the hang of it, its a pretty good program.