Well, you can do it wirelessly, but you will probably find that it takes forever - I'd suggest, at least for when transferring huge files like the size that fraps creates you'll most likely want to just get an ethernet cable and for the time to transfer it, just hook the Macbook into the switch on your wireless router (which is what I assume you have).
Some people find it easier to do the drag and drop on the PC side, so the easiest way to handle it is, on the Mac, in your home folder, there is a folder named Public - Right click on that folder and select Shared Folder.
Also on the Mac, go into System Preferences->Sharing. Enable File Sharing, press the options button on the right and make sure you select "Share files and folder using SMB (Windows)" and click Done
Before exiting the system preferences, you should see where it states computer name - jot that down. Go to the windows PC, open up Explorer (windows key+E), click in the navigation bar/location bar and type \\YOURSYSTEMNAMEHERE\ and press Enter
it should now list the shared folders on your Mac.
Open public
You should see a folder in there called Drop Box - drag the video files into that folder (the default settings you can't write directly to the public folder, but you can write to the drop box). Once the files are transferred, go to the Mac, in your home folder, open the Public folder, in there you should see the Drop Box, open it and move the files to wherever you want.