Theres two main types of wireless headphones. 1, infrared. which means they must have a direct line of sight to the transmitter and FM which uses the FM radio waves to transmit, so you don't have to have a direct line.
If you want to be wandering around the house with them on, then you want FM based ones (i do this sometimes listening to music whilst cleaning or whatever).
Do note that the transmitter with most likely (if not definatly) require a mains socket to power it, so you're laptop will need to be near a socket. Although whjy you need wireless headphones sitting at a laptop i don't know
