MasterLich
Watchdog
Why not. One field for hardware and one for OS or do you have anything else in mind? It shouldn't be too detailed though, a hardware list (including consoles) can quickly grow too large, better let the user decide about the specifics.
I think that one free-form text field for all should be enough; after all, there might even be some console users here. Or someone might want to list more than one machine (e.g. a handheld).
EDIT: Unless you consider something like max. 120 characters too large.