If you have a USB wireless card, then you can tell your Virtualization software (VirtualBox, VMWare) to pass the card to the Guest machine (BT5). That means that your host (Windows? or whatever you use to run VBox/VMWare) will not have access to the card, only the guest will.
As gunrunr wrote, you can simply use Bridged mode just to connect to a wireless network so you can still run a myriad of tools, except for the wireless ones.
Small tip @being a beginner: I would start by installing Ubuntu in dual-boot mode if you have no previous Linux experience, and run VirtualBox in there. It's very simple (and much safer) to use, and will give you a chance to really get used to working with Linux. Since BT is based on Ubuntu, a lot of the same principles apply (apt-get). The key to success is practice, practice, practice