On my laptop for work, I use several different networks, both wireless and wired. I need an easy way to switch back and forth between all of them. I use network manager (gnome) to connect to the wireless, and I really like how you can click on it and view all the available wireless networks.

The first issue I'm having is that when I switch it over to 'wired network', to set a static IP, I have to disable roaming mode...which then prevents me from connecting to wireless networks until I enable roaming mode on the wired network.

I'd like to just add additional options to that menu (up where it says 'wired network', that when selected, would assign the computer the proper static IP and gateway and put the computer in 'wired' mode. Can the gnome network manager be modified to do this?

You may try wicd.

Don't go there!
It messed it up for me really good!
Installing it by using Synaptic+new repository removed network-manager and I lost network connection. The daemon couldn't be started and none of the tools. I may be stupid and lazy enough to not read any documentation that might have guided me but that is also true for any newbies for any number of reasons. If it starts off by killing my network connection and thereby preventing me from easily reverting it (I had to restore network-manager from CD), well, I'd hate to see any newcomers getting grey hairs over this.
At least, read up very well on what it does.
/Lakris

I'm not really a new linux user. I've broken network manager enough times though that I don't want to screw with replacing it...especially when it can connect to my wireless so easily. Remember getting the Intel pro stack to work in dapper? been there done that.

If I write a script to manually configure eth0 (by writing to /etc/network/interfaces), will that screw with network manager and make it not want to work?

Hehe, and I really didn't want to bash an effort like wicd just like that, only warn the less wary (like myself).
My first reaction really was WTF!?
Yes, a direct edit of /etc/network/interfaces would do I guess, but I had lots of different connections configured in network-manager and that would be a pain to configure again in any other tool. Not that nm is a very great or versatile tool but I've grown used to it all the same.
And to Your first question, I haven't had that problem but for example when I need to have different VPN-connections active at the same time I have to use open-vpn alongside nm.