Well I foud the same thing on my machine (7100).
Compared to even vista, browsing folders with large numbers of media files was a crawl. By default Windows 7 is trying to suck information about the files out, posibly even creating thumbnails or indexing them on the fly. The automatic “Let me put you into picture view mode because you have one jpeg in this folder” “Feature” is REALLY REALLY ANNOYING!
But for 7100 the problem was WAY worse for some reason. Anyway, as in most every other version of windows, I go tot he root of the drive and then to the folder settings (“Customize”) and set the current folder view to “general files” or “general documents” I think it was called (It changes name every OS). Then select “Apply to all folders”.
That makes it show nothing but the file system info for each file like ghod intended, no thumbnails, no id3 tag parsing, no jpeg header parsing, just size, date, and name. Opening large folders is again instantly fast.
You may have to go back to certain folders you wanted to actually be in icon view and set those again, the preview and icon modes are not bad IF *I* get to control when it does and doesn’t happen.
Course unfortuantely you eventually run into the bag mru limit problem and after a few weeks or months Windows starts randomly changing your folder views on you again… I really wish tthere was a single place you could just turn that off completely.