I have tried saving to my computer from the SD card and viewing directly from camera to PC.  I have tried two different SD cards, SAMSUNG: EVO Select 128GB MicroSDXC UHS-I U3 100MB/s Full HD & 4K UHD Memory Card with Adapter (MB-ME128HA)  and a Sandisk card with the same specs.  Every video has issues with skipping and lagging during playback whether saved or viewed directly.  When watching the videos on the camera screen there is no problem with play back.  Please let me know what I can do to save these videos of my daughter on our vacation!!!  I'm hoping I didn't make a mistake by choosing this camera over GoPro.  If I can't get a solution I'll be returning this and going with the Gopro instead.

Hi, cvmacfie. Thanks for reaching out! We suggest checking the resolution of the videos you're having trouble viewing. If you're shooting in 4K, kindly shoot in lower video resolution and test if the problem would continue. You can also use a different media player to playback the video on your desktop.

this is not the cameras issue, it is your Computer.
HDD
graphics card

try VLC player