Thanks. Now, of the 20,000 images I've taken on the D40 so far, none were RAW. I didn't even think about it actually. I also didn't risk shooting raw + jpeg as the D40 gives the option of basic jpeg if Raw is used as the primary option.
So basic questions -
a) How long does it take to convert a single image into JPEG if shot in RAW?
b) I assume I wont be able to view anything on screen if I shoot that format? So how do I check if the image came out 'OK'? I've been using the LCD on the back of D40 to check if the photo came out OK.
p.s. based on the previous poster's suggestions, I'm leaning towards D7000 now as am so far shooting only JPEG.
For me, RAW is the only way to go. If you shoot JPEG, you "throw away" lots of information, so your postprocessing capabilities are greatly reduced.
a) On my computer (Intel Core i7-3770K 3.50GHz) running Debian Linux with Canon DPP via wine it takes about 3 seconds per image from the 5d. But this number depends on the postprocessing steps selected for the image, e.g. if you enable noise reduction it will take longer. Unfortunately, DPP does not use the multithreading-capabilities of the CPU (yet).
b) Yes, you will be able to do so. Each RAW file (at least of Canon cameras) contains an embedded JPEG preview file, which is used by some programs for display (including the camera itself, which displays the embedded JPEG on the LCD). A program that I use for quick previewing the RAW files is geeqie (on Linux).