If you have just upgraded to Win7, you are probably pretty pleased with the new Windows Explorer.  Lot's of nice productivity features like being able to display a folder and its sub-folders as one thing.

One of the issues you may have run across is the fact that Adobe .pdfs so not display in the preview window even after installing Reader.  Apparently an installer issue.

Here is a tip from Ditti to quickly resolve it.   If you have a 32 bit version of Win7, just take out the Wow6432Node\ when you are looking for the registry key.

Once the key is changed, it works like a charm.

http://www.ditii.com/2009/09/11/fix-for-adobe-pdf-preview-handler-bug-in-64-bit-windows/

Pretty simple, but I was hoping it would be a couple of weeks before I would have to use regedit on Win 7. Oh well...