You need to have a wireless router to which your BB router has to be connected. If you are going to use it for desktop, you need a wireless PCI adapter or wireless USB adapter as well. But AFAIK USB adapter is the best.
If you want to download large files like movies, etc., i would suggest you to use wired ethernet connectio as it would be fast and there wont be any connection drops. For small tasks like checking mails, browsing, etc you can use wireless.