Then there is definitely something wrong with your brakes, as others have said, the brakes should never perform like you explain. It's difficult to say exactly what the issues is from what you've posted. First check would be to see the brake pad condition and what type they are. Abviously as well as the issue with sticking calipers.
I tried a set of (free) 'Green stuff' pads once, the performance was so bad I'd say they're dangerous to use! After I used them for about 300 miles I chucked them away and bought some Chris Wilson fast road pads (along with new discs, etc) have never looked back.
I wouldn't necessarily say Toyota is the best point of call, they are very expensive and unless you're lucky the mechanics are not all that useful on the older cars. It would be better to find a good specialist in your area (or even further afield).