Orange broadband cancellation

macman

No, very few ISP's will allow you to cancel after connection-that means that they would have to write off all the one-of costs of connecting you. You are now outside of any cooling-off period.
First thing to do is to retest using ethernet-if it's OK, it's just your wireless connection, which is not Orange's responsibility anyway. If that solves it, the second thing to do is to log into the router's web interface ad select a different wireless channel. Download and check for neighbouring channel conflicts using InSSIDer.
But the Orange Livebox is a notoriously flakey bit of kit, much easier in the long run just to go onto eBay and get yourself a decent router such as a Netgear DG834G for about a tenner. It's unfortunate that you chose to go with one of the worst rated ISP's around (why did you swap from Sky?) but now you're in contract you'll have to make the best of it.
Don't bother with Orange tech support, you'll get much better support on here!