Configure router for Nintendo WiFi access

[Meatball]

Does anyone know if there are any specific settings I need to use to use my Nintendo DS over the internet (Mario Kart)? My router is a WGR514v5 if it helps? . Whenever I try and connect I get an error code 86420

 

[Meatball]

Well I turned off security entirely when I got Mario Kart as I couldn't be bothered with it. I trust my neighbours and they trust us so hopefully nothing will happen (they have unprotected networks as well). I managed to get better connections with my DS by turning off the firewall on my router.