Just because there are Vista drivers does not mean it will work with Windows 7. The answer to your question can only be found by actually hooking it up to a Windows 7 computer. It is old Wireless G technology. For the price of postage your friend could have wireless n.
In any event Belkin says
Windows 7 Product Support Information
Windows 7 users:
If you are using an older Belkin Networking product, you may not have support for Windows 7 with your current software.
Software updates will be posted as they become available. Please check back if your product is not currently supported.
Some updates may still be in the process of going through Microsoft’s official certification program. Although they have been thoroughly tested, they may present a warning message when the driver is being installed. These drivers will install on 32 bit operating systems but not on 64 bit systems, which is the normal and expected behaviour.
Even though your product may currently not be supported under Windows 7, it may very well work on it; in the majority of cases, software and drivers for Windows Vista will work on Windows 7 without a problem.