I have a problem on my driver side disk brake, i think its kinda stuck.. when i turn the wheel by hand its kinda hard to turn and it makes some clicking noise..

what could it be?
is the piston supposed to be like this?

 

Clicking when turning sounds more like axels, are you hitting brake also when turning? Could be rotors or caliber, both pretty easy and cheap to change

 

Your pads look ok, get a set of rebuilt calipers. When you push on the brake pedal, the piston pushes out due to hydraulic force via the brake pedal. When you let up on the pedal, the piston should suck back in just a little, yours is not doing that. It more than likely is corroded up internally so when you do the swap, pump plenty of new brake fluid through also to get rid of the water that has collected in the hoses also.

You may even get a good deal on loaded calipers (with pads).

 

The clicking is when braking...


either turning or not..

so, i just need to change the calipers...??

 

That will be fine, while the pads are accessable, take them out and rub them on the concrete in figure 8s until all the pad surface is not shiney, then reinstall them after the caliper in in place. Can you take more pics for the archives please, what do you have to assist with brake bleeding to try not to make a big mess out of the job. Ask about 4 new copper or aluminium washers for the brake hose to caliper fittings, you can even change these lower brake hoses if they are not too much, it all depends on your budget.