By "dolphin" do u mean the Gc/Wii emulator?
"go to configuration and map the keys for Player1 (use keyboard) and map keys for player2 (use a control plugin [game pad].
Please tell mee if I’m close…
Try a Wii remote (if you have bluetooth).
If I recall in bomberman blast you had to access the main menu with the wiimote "then" you can use the GC pad. I’m not if it helps but its worth a try…
Oh I’ve read in the Dolphin forums (old post) that Gc support somewhat wasn’t working. Have you compiled/downloaded the latest build of Dolphin?