If you are not using IrfanView as the default image viewing program on your PC, you are doing yourself a SEVERE disservice. Before you read the rest of this post, go to the IrfanView Official Homepage and download the program and the plugins, install the program, install the plugins, and let it associate all the file extensions with IrfanView. Double-click any image file and note that it opened more-or-less immediately. Hit the space bar on your keyboard and the next image is there. Hit backspace and the previous image is there. It works with pretty much all image file types, and can even read some partially-corrupted images.
I have been using IrfanView since the years when it actually mattered that the entire program can fit on a single floppy disk. It is one of the first programs I install on any new machine. I like it so much I actually donated my own money to support the program, and I NEVER donate to shareware/freeware authors.
Anyway, I just realized as I was sifting through a pile of images on my camera's memory card that when you hit DELETE on the keyboard, and it gives a confirmation dialog, and you hit Yes or the Enter key - it deletes the image as if you had deleted the file in Windows Explorer. My previous method of doing a first-cull to delete throwaway images was using the Filmstrip view in Windows Explorer, full-screen so it shows up a big image. With IrfanView, it can give a fullscreen image, and hitting control-H shows the actual pixels so you can see every last detail. Windows Explorer resamples in a not-great way but IrfanView shows a very clear image on my monitor. My life just got more efficient. Thanks to Jesus! (and to IrfanView!)