Which Admin Utility version for old 802.11g Airport Express?

Question

Which version of the Admin Utility should I use for my Airport Express which is about 5 years old, maybe more? 
And what about firmware updates? I have Windows XP.
My Airport uses 802.11, 802.11b and 802.11g, not the current 802.
Currently I have Admin Utility version 4.2.
The Airport won't recognize my networked hard drive and my only hope is to update the software.

Answer 1

I believe WDS won't halve the bandwidth on the master, only on the slave (which won't matter, because it will be more than fast enough for airtunes). And the extreme will be faster than your modem anyway, even if the bandwidth were to be halved. Unless you've got some seriously fast contract. But in any case, I doubt it will work using one of the other methods. I had this problem in the past (as it happens, my b/g AE died, and I now have two n units, connecting using 'join'), and I wasn't able to make it work using something other than the WDS option. But you could always try yourself of course. If you put your b/g AE on ebay and buy a b/g/n unit, you'll be able to use the join and extend options.
Btw, you don't have to disable the WAN port on the express, because it actually isn't only a WAN port - it works both ways. You could connect it to a blu-ray player that wants to connect to the internet for example, or any other device that has an ethernet port.
But yes, you have to connect to both routers together, as one network is what you want. And to answer your last question, I'm pretty sure that airtunes will first go through the extreme, an then to the express. But why don't you set it up in WDS mode and see how you like it? I certainly had no problems with it when I had the b/g AE.