Hi zantgo, Diablo 1 is actually one of the very few games i do play on my computers.
Yooy is not correct about the cd needing to be mounted in the same place as when installed. In my experience, wine is good at locating where it is mounted.
To get it to work, insert the cd and open it up in your file manager, once that's done, if you open the game it should find where it's located automatically.
Additionally, if you're anything like me, you won't want to carry around the cd all the time. You can get around this by ripping an iso of the disc, and keeping it saved on your computer. That's what i've done and it's 638Mb.
If you do this, all you have to do after that is, 'sudo mount /location/of/saved/image/Diablo.img /mnt' and then Diablo will work like the disc is in side the cdrom.
lastly, The game plays perfectly, but the start menus are screwed up and only display black.
I run kde, and it is actually possible to view the menus if i activate the 'present windows' effect while the screen is black; or if i press alt-tab to go through the open windows thing.
Doing this makes it possible to setup, half blind. Without them effects you'll be setting up completely blind. Once the initial setup, character creation ect, it's easy to get into your saved game, by just pressing enter until it loads, and then it's smooth sailing.
That all sounds a little complicated, but it's very easy.