Browsers war on my PC

I have switched from WindowsXP to Windows 7. So far, so good, better that Windows Visa. Anyway, as a web developer I have to have all possible browsers on my computer, so I can check cross browser compatibility for websites I develop. I installed all of them (IE8, Opera, Firefox, Safari, Chrome) and I just faced a series of questions: “Would you like to make xxx your default browser?” The point is, during the fast flow of work I just click “no” without selecting “Don’t ask me again,” so the question will come back. Anyway, I selected Chrome as a default one.