Yeah, scanning film with a flatbad is probably not optimal. But to be honest, I just want something good enough for presentation on the web, and I don't want to spend the time or money making prints.
There are two kinds of flatbed scanners, those that have a single lighr source below the glass, which are lousy for film, and those that have a second light source in the lid or cover, which works better for film. Most of those work well with 35mm, although the enlarging can result in pixelation. Pixelation is an effect that if each pixel is 1μm in size, and is enlarged 1000 times, each pixel will appear to be 1mm in size. This is the same effect that low resolution digital cameras can produce, it looks sometimes like grain, but really ugly grain.
Another way of getting a scan is to print the negative on silver paper as a 4x5, then scan the print in reflective mode, the printing process will reduce the DMax to a more scanner friendly level and eliminates pixelation.
For the web, you can usually get good enough results using a negative scan, keep your images small and use a reasonably high Jpeg compression ratio. I recommend that you imprint copyright information into the image before posting. The reason for keeping images small and using a high compression ratio is that there are still people using dial up connections. :rolleyes: