I want to get some headphones that I can use, and perhaps ds1 (9yo) as well. I want them to cost under 100 quid. I will be mostly listening to music from CDs, in the house, possibly while on my exercise bike. I want over-the-ear ones as I always find the in-ear ones uncomfortable (they seem too big to fit in my ears) and I don't care if they look stylish or not! The type that let you hear other stuff in the room would probably be appropriate as I don't necessarily want to block out the boys' cries for help while I'm exercising. 
What should I be looking out for? What kind of frequency range is reasonable? I am nearly 40 so I would expect my hearing to have gone at certain frequencies, but I know that if I'm listening to stuff in the car I can often tell if high frequency bits are missing. (But we don't have a car at the moment so I can't check the specs this way.)
Waiting for a headphone geek to come along and tell me exactly what to buy!! Thanks.