Make a new DWORD value named ThumbnailSize. Double click the value and type in a number in decimal anywhere from 32 to 256. Making it smaller will display many more images on the screen for quicker perusual. Its an immediate change by the way, so keep regedit open and mess around...
It does nothing. Is there not a command somewhere that sets current view to default? Or a way to change this that actually works (The ONLY thing I can think of is this setting works only under 32 bit, not 64 bit, and I have a 64 bit os. Starting to regret it..)
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Are you sure you don't have to restart Windows/Explorer (after closing Regedit, etc. of course) to see the changes? Most things you have to for the change to take place.
If you don't want to restart Windows completely you use a task manager (I use Sysinternal's Process Explorer) to kill explorer.exe (if there's more than one make sure you choose the right one - you'll lose whatever folders are open and your Start Menu/Desktop will disappear briefly, even with the right one, but all of your other apps should stay open). Make sure you use "Kill Process" and not "Kill Process Tree" or you will lose more than just explorer.exe; whatever was "under" it if viewing Process Tree - Ctrl+T). Then just hit File/Run (Ctrl+R) and enter "explorer" to restart. Your registry will reload with the new changes, Start/Desktop will come back, etc.). If they don't just run explorer again like before (even if you see explorer already running). That should bring every thing back with your changes.
DISCLAIMER: Do all of this at your own risk. No warranty given or implied!