If it's a BMP file being selected, then BMP will be the default save file type. If I right click a JPG, PNG, GIF, etc... it gives me that file type in the drop down.
See what you get with these examples:
JPG---->
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PNG---->
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GIF---->
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If all the above say BMP, I would start by checking file types and associations.
CLICK--->My Computer/Tools Menu/Folder Options/File Types TabMake sure all your file types are listed and configured for default actions:
only the jpg portion of the file list is displayed in the example below
Sometimes new software installs will change default file associations. Example would be when quicktime opens all movie files after installation, or a newly installed Photo Suite opens all images.
You can configure default associations in the File types tab...
Thats bout all I can think of off top of my head...
Mike