All 3 are great suggestions, sound-wise and price-wise. Here is my experience with them.
KSC75 - very light, rests on the backs your ears (no headband)
PX100 - very comfortable and light, folds up for portability
SR60 - the cushions can get uncomfy, but you can replace them with comfier ones for cheap or flip them inside-out; these are like one of the starter headphones for audiophiles so they are highly recommended
So none will hurt your head, but I've found that the Grados can (YMMV) make your ears tender after a while since they sit on top of the ear (supra-aural) instead of around it.