As long as you have connected then the WEP or WPA secuirty key is correct, so dont worry about that.
What ISP are you with?
When you intially joined up you would have had some advanced settings with DNS settings etc to manually enter. If you have lost these it is not an issue your ISP will either re-send them or have them on there help / FAQ page.
Otherwise a bit of searching and you should find the correct settings on a forum.
If all the settings are correct, it may be worth checking what version firmware you have on the router and if there is any updates currently avalible from Netgear.
Hope this helps.