Hi, yes the mk2 disks, pads, and calipers will fit onto the '96 mk1. But as Richard says above you might want to take a look at what is wrong with the current setup first. In order to fit 1.8 brakes onto a 1.6 you don’t need the calipers, just the carriers. These will space the calipers out to accommodate the larger disks. mk2 pads will need to be used.
Mk1 1.6 brakes are actually not bad, so I would first visually check your current setup for plenty of pad life, then remove the calipers to clean the sliders and grease then with the proper brake grease, then bleed the brakes thoroughly. Whilst you are at the rear brakes take a moment to re-adjust the freeplay in the pads with an allen key so that when you push on the pedal you’re not taking up lots of slack all the time.
Finally check the state of the vacuum tube between the engine and brake servo to make sure it’s in good condition. If this is bad then you will probably have a rough running engine as a clue anyway.
If you do that list of routine maintenance (which should cost you only about £12 in grease and brake fluid) and the brakes still feel bad then take a look at the pedal freeplay in the footwell.