What concerns France : the French law (25 july 2003) makes the distinction between using inside houses (channels 1 - 13 ; power limited to 100mW) and using outside houses (channels 10-13 ; power limited to 10mW), but maybe France will adopt (or has adopted  ?) the more flexible European rules for using outside houses.

I don't know it for sure but I've used both channels 6 and 11 and once I was connected to channel 1 from a neighbour (it was not on purpose, its IPs and channels had lower numbers than mine so in Linux I had to state the SSID manually ).

So all I can say without investigating is that you can use from channel 1 to 11. I will try to check it better; if k0ga were reading this post surely he could help you better than I do.