Good to hear your camera is working well, I updated 2 of mine to 20131026 firmware yesterday, and after about 18hrs testing it does indeed appear to be a good stable firmware version. Certainly no issues here.
Most of us tend to use a free program available online called REGISTRATORVIEWER.EXE to replay the video files, it also handles the GPS logs too showing your position on a google map. Make sure you use version 5.3 or later or it wont read the GPS logs files properly. Its a single executable file, so can be run from virtually anywhere on your PC or directly from your camera if you copy Registrator to the root directory of the card, just bear in mind that it searches the current directory it's run from to locate the video and GPS logs files, it will then search any directories that may be within/below that same folder you ran it from.
It does sound however as though your computer system may be a little slow, with perhaps a older graphics card, or is the graphics built-in the motherboard, ? the symptoms you describe do appear to indicate a slow system.
Did you download Techmoans original video files which he gave the link to on his site, if so how well did those those play back, were they still stuttering ?, and lastly, do you copy the video's to your hard drive and play them back from there, or direct from the camera or perhaps a usb card reader or pen-drive ?
