Help with which black Indesign

Hi When specifying a black background for a flyer which will be both on web and as printed flyer I am getting really confused. My flyer background is C0M0 Y0K100 in indesign ( indesign standard swatch, in preferences display of black overprint unticked. In the flyer placed is a photoshop image with black background filled with black,edit-fill-black, double click this black swatch thumb and it confirms C0M0Y0K100 in PS. When i export to PDF my flyer background looks grey compared to the black image BG from the placed PSD image. Why is this? I went on a google search about which black to use but am still confused about all the blacks, I have the following to choose from..

RGB Black | R/0 G/0 B/0...this is for the web flyer
PhotoShop® Black | C86 M85 Y79 K100
Neutral Rich Black (also known as Rich Black) | C40 M30 Y30 K100
Flat Black | C0 M0 Y0 K100
Designer Black | C70 M50 Y30 K100
help ! which black generally for my print design work and is it a case of inputting the numbers to specify it in PS,Illustrator,Indesign and all will display the same black? Many thanks. Sam

I always use Registration Black in indesign.

I always had the same problem(black looking gray when printed and exported as a pdf) and I don't know why it happens.

You need what is called a rich black - black is just that and uses 100% black ink - which is what you want if you have black text on a white background.

Create a separate swatch, dont go overboard like 100% of all 4 inks, that will create problems on printing presses

A typical rich black that will look blacker would be 30C 30M 30Y 100K

Notice that if you add the numbers up you get 190 - many printing presses do not like more that 200 to 250% ink coverage so that rich black keeps the press from putting too much ink down (which can soak the paper and cause it to warp).

For print we use a rich black of C45 M35 Y35 K100. Make sure the text is not rich black though, registration problems will stick out like a sore thumb.
Web presses should keep total ink density under 280% for coated stock and under 260% for uncoated stock.