Are you using a third party launcher? If so you can just hide it. Or just remove it from your homescreen if its there. Long press on it and then shove it into the trash bin.
As for so that no other app opens it, go to menu>settings>applications>all (its a tab at the top)>internet>clear defaults. Everytime another app wants to open a web page, if you have another browser installed, it will ask you if you want to open using the default internet app or the other browser, set the default to the other browser.