Hey guys

So i have decided to go wireless and had a look at the Airport Express that has a lot of options and possibilities. I only have one last question. I currently have a desktop connected via LAN to a Telkom (802.11g) router with a ADSL line. The Telkom router has wifi but only in 802.11g form. (Ipad2 only supports 802.11n ???)

Q1: Will i be able to connect to the internet from my iPad via Airport Express(802.11n) to Telkom(802.11g) Router?
Q2: Does all of these need to be on one form i.e. 802.11 a / b / g / n ?
Q3: Will i be able to connect to my iTunes on my desktop from my iPad?

Many thanx!