BIN file is a binary file (or an image) containing the information in the disk. CUE file is a... well, it's a cue for a virtual disk reader that tells a program where to find the information.
You use them by either burning them onto CD like Flipside said, or if you have spare disk space you can simply use the files from the HD. That requires downloading and installing for example Daemon Tools or Alcohol 120%, and then you create a virtual disk and open the CUE file in it, and that will mount the disk image to the virtual disk. Then you use the virtual disk like any other CD, except that the data is not physically on a disk, the software just makes your OS think so... for the most part anyway.