The old inventory screen for equipping stuff, checking items and monitoring stats. Also note the funky stone look of the interface, another nod to Baldur's Gate and a demonstration of the early GUI's re-skin-ability (new word there) being, as it was, possible to change the tiled texture of the interface to anything you like.
..Then I went a little minimalist and booted out the whole interface in favour of something that took up a lot less screen space.. Mad, I know, but what I learned while doing all this has come in enormously useful since.