I bought the Bounty Pack almost 10 years ago and it doesn't cooperate too well with newer systems.
There are two solutions (only one of which I've ever tried).
1) It runs great in
ScummVM.
Just install ScummVM, copy
these files to your hard drive and
add the game to ScummVM.
2) You can also use Quick and Easy Software's
Curse of Monkey Island Setup Wizard. They also have an
alternate launcher for the game.
However, even they suggest that there might still be bugs and quirks and suggest that you use ScummVM instead.
Other advantages of ScummVM is that you it lets you play your game on different systems (I have tried it successfully on Mac and Wii, but they also have ScummVM for Linux, PS2, PSP, Dreamcast, iPhone,...) and they also offer a few freeware
old school adventure games (Beneath a Steel Sky, Flight of the Amazon Queen, Lure of the Temptress, Drascula).
As I was typing and linking, I noticed that Alex IDV has been helping you and concur with him that ScummVM is a great way to play Curse of Monkey Island.