I've had one for almost 30 years and tho they are HEAVY to move around and then use? They WORK and keep on working!
That 'paddle' is the equal to two 'beaters' on another mixer and will make cookies a sooth as silk when you cream...say butter and sugar for cookies.
The Hook is a dough hook for making bread doughs or pizza doughs etc. There are likely lots of recipies on-line for any of the attachments, basic or the extra ones you can buy....you just have to know your model # and other key info stamped on the machine to find out 'compatable' attachments. Such as the 'pasta' makers ...one a roller and one an extruder for macaroni's. Finding attachments to 'fit' your particular model can be pricey? But the machine is hefty and all pieces will work hard and long for you. They prove worth in the long run.
It is one true LIFETIME appliance. I've had other 'stand' and 'hand' mixers and none compare to the Kitchen Aid! You have a treasure, so now learn how to expand it's uses! - j