I'm not sure if all scanners that can scan film work like mine, but I have a hp scanjet 5400c, and it has a special attachment that lets you scan negatives and slides. You slide the negatives or slides into the attachment, and place it on top of the scanner bed. Then, when you're saving the negatives, you can either save them at negative size, or 300% magnification, which ends up being just about the size of a normal print. I think they're saved as TIFF files, but I'm not sure. Its a very handy contraption, very easy to use. Hope this helps!
yep; they do exactly that. i have an older model: a canon 2700f. it works perfectly well for slides and negs. what i can't tell you is what scanner is the best for the dollar; i know diddly outside of my little scanner's world.
For someone on a budget looking for a film scanner, the Minolta Scan Dual III is probably the best option at the moment. 2800dpi/48 bit colour depth, with a dynamic range of 4.8. It goes for less than $300 at many places in the US ($289.95 from B&H, for instance), and has many favourable reviews. What it doesn't have is Digital ICE.