For years and years I used to grab the lower right hand corner of the open file dialog box and make it as big as possible, then I'd see my folders quickly. I found the scrolling tedious.
There are a few programs around that permanently resized all dialogue boxes for you. OpenWide is just one of them, some charge money, some don't.
I'm always amazed that Microsoft don't pick this stuff up, - it is simple basic ergonomics.
I open many dialogue boxes every day so this really is nice. The next thing I'm looking for is a quick and easy and freeware solution to 'paths'. My ideal would be: the last 15 most frequently used locations on my disk in order of frequency of use listed. One click and I'm there ! That also would be a great little solution. There are some that do this around.... but not as well designed as I'd like yet...