Yes you should always be using the 802.11 standard, try using N as it has greater range by default. As for the passwords and signals, not sure, I don't think you'll have two signals and if you don't then there is no need to worry about two different passwords. Performance with these vary, it depends on what type of system you are running, how much bandwith you are taking up etc. I personally would always choose the linksys, cisco invented the router so they are the authority when it comes to those devices. Good luck.