Dunno why I'm replying after Saturday, but here we go anyway.
As an earlier reply says, you can use as many laptops as you wish.
If your router is anything like ours you can also connect to the network connections on the router directly to your laptop/PC. This will ensure you get maximum speed at your laptop/PC. When using the wireless connection, your internet speed is dependant on how good your wireless signal is, i.e. the further away from the router you are, the slower things become.
If you're using a laptop for the telly (which I suspect you are!), I'd hardwire that to the router using a network cable.