There is a game that I've been searching for the last 15 years...
It was a "pac-man"-like game, but I don't remember ghosts (maybe they were, it was a long time ago). I knew there were some other elements of gameplay, as balls fired from pirate cannons in one level, which killed you when touched. I remember other couple of things: in one underwater level, music of the little mermaid ("under the sea") was used, and in another one, some music from star wars. Also, there was certain level in which a black ball you thought your friend would divide in four and be the enemy for that stage.
Another notable thing is sometimes you could get "out" the walls of the map by secret passages.
At the end of the game, you had to set a self-destruction count for something, and get to your spaceship before the time ran out. After that, some kind of animals congratulated you for saving the world, and there were fireworks too.
Sorry for not giving many details, but those are all which I recall. Hmm... and it should be before 1999. The game was on 2d as well, with front perspective (as the normal pac-man). I've been seriously searching it like crazy in hundreds of cds and floppies many times, but I think I just don't have it anymore.
EDIT: Platform was either Windows 95 or 98, don't remember.
Thank you very much for the help, and I'll be trying to help the others as well!
P.D: Sorry for any typos, I'm not english...