Installing worms forts under siege?

My little brother wanted to play the game, so this morning he inserted the disc, and installed it. It worked, and he left it to go eat breakfast. He came back, and it wasn't working. He is convinced that it has something to do with him uninstalling Roxio Burn. I tried opening it for him, and it opened as far as the page where you install it, then windows downloaded came up, then a picture of the game with a button finish underneath. When clicked, I got a notification saying the installation didnt work. HELP.