If you like to make use of the image preview thumbnails which Windows XP and Vista make available in the Explorer folder, but think the size is too big or small, change it.  You can make the size of the thumbnails anywhere between 32 x 32 (the size of an icon) to 256 x 256 (quite a bit larger) by making a change in the registry:

  1. Open the Registry Editor (Start > Run > regedit).
  2. Navigate to the follow folder/key: HKEY_CURRENT_USER > Software > Microsoft > Windows > CurrentVersion > Explorer
  3. Add a new DWORD entry called “ThumbnailSize”.
  4. Set the value to be any number from 32 to 256.

Once you make this change, your image previews will still be proportional, but no larger than the value you specified in the ThumbnailSize entry.