I have one adsl modem/router which is not "top" of the line and it lack allot of options which I need. I was able to acquire one Cisco router recently which has all options that I need ( like DMZ, VPN, port forwarding, etc). I'm interested, if I connect the old modem/router to new Cisco router using bridge mode, will I be able to use all the features on the Cisco? For instance, the old router is lacking of port forward options. Does this mean that I will not be able to use port forwarding on Cisco router either or, since I will be using bridge mode, this will not affect Cisco router and it will work as the modem is in him?

thank you