How to burn Windows compatible CD on Mac OS X Mountain Lion
From http://support.apple.com/kb/PH10699?viewlocale=en_US (it applies to OS X 10.8 "Mountain Lion"):


  You can burn files to a CD or DVD and then use that disc as a backup,
  send it to friends, or copy the files on it to another computer.
  Discs you burn on your Mac computer can also be used on Windows computers and other types of computers.


You just have to follow the instructions in there. If you prefer, you can read more detailed instructions here: http://www.dummies.com/how-to/content/burn-cds-and-dvds-on-the-fly-in-mountain-lion.html

Both guides come down to this:


Insert a blank CD. 
When the disc appears on your desktop, double click it and drag the files you want to burn into the window.
Then press the "Burn" button in the top right corner of the window, change disc name to something that makes sense to you and press OK.


Make sure you choose a CD type that can be read on your Mac and your Windows machine. For instance, check that CD speed and capacity are supported by both optical drives.

If you wish to reuse a disc (CD-RW/DVD-RW/DVD+RW) you have to erase it first using Disk Utility. See http://support.apple.com/kb/PH5849 for more information.