Changing Router Channel - Two Questions

Hi,just two little questions, hope someone can help :)Sometimes my W-LAN Router has problems. All devices are still connected to it but they don't have internet access. I have to restart my router everytime if that happens.
I found out, the problem could be my neighbours who are using the same router channel. Now I want to change my channel to solve that problem.My router is actually set to use channel 6.
Is there anything that I have to consider when changing the channel?
I also heard Wifi for NDS is only working on channel 1 to 11 is that true?

it depends where you live.some regions of the world have 11 wifi channels, some have 13.HOWEVERThere are only actually 3 channels you can use, regardless of where you live, and they are channel 1, channel 6 and channel 11. All other channels overlap these 3, resulting in a higher chance of interference from other wireless networks. You want to choose the channel from these three that has the fewest other networks on it.

Ok, thanks :)