Offline System (Armory only if I recall right...)
The offline system is completely uncritical. It doesn't need bitcoind nor the Armory blockchain, so 100mb free HDD space is enough. CPU and memory wise, a Raspberry Pi is already sufficient. This means that *any* computer you are able to install a recent OS on will be fine with offline Armory. I highly suggest Linux for this.
It got much, much better with the online system too. Before, you needed around 8 gig memory. Now a "normal computer" is fine. Others will chime in what this means in detail (more than 50gb HDD for example).
Ente
Ty for that, I know shit about linux aside from my limited experience with my cloud VPS.
So that said, it would be I guess as you said, at least for offline, any old laptop I can get my hands on with at least one USB port running XP, Vista or I guess 7. However XP is the only OS I have a copy of.