router/modem and 3DS?

[J]

Hello, I'm not tech savvy guy and trying to get down to why I always have problems with my internet. Mainly on people with 3DS.

Is it a firewall setting or something?
I'd also like to know the optimal settings for my router. It's a WNDR3400.
http://media.materiel.net/live/113681.jpg

My modem is one that came from the cable company that is both connected to the cable and phone. http://images.quebarato.com.mx/T440x/mod...CDA0_1.jpg

Should I get a new router and/or modem?
How can I get wi-fi without relying on the phone line? What settings are the best setting I can use for my router? And what can I do so the 3DS can have less problems with it?

[Waylon]

check your settings.