putting new pads / discs in

Hi I just replaced the pads on my bros 1.2 SXI Corsa D. I was wondering is it similar on the 197 bar there being 4 pistons instead of 1?

When changing the disc is just a case of taking the special screws out and putting a new disc on? I shouldn't need to bleed the brakes right?
 
Probably easier mate. 2 bolts take the caliper off and pads are on pins