Good thing it's on a LAN because AFAIK you can't get the MAC addy over the Internet [although I'm still looking into how it would be possible to do it :)]. If you're good at code why not inspect the nmap soft at www.insecure.org and get ideas from there? You could use that program but I think it's a bit more than what you need and it wouldn't be the most effective thing.
On the other hand... since you said you need to extract the IP too, I'm wondering how you'd go about knowing which computer you want the info from? I guess you need a client/server type app with the clients running on the users' computers... and have them double click the prog name and that would send the info to your computer. Me not being a guru when it comes to XP scripting, I can only say... wouldn't something along the lines of
ipconfig/all > c:\info.txt [as said before]
net send IP info.txt
work? Or maybe
ipconfig/all | net send IP
but I'm not sure how [if?] piping works in XP. Also not sure about net send syntax, that's easy to find from the documentation you have on your computer.
