What model of camcorder is this video from and what format and resolution is it?
Your processor is pretty minimal and probably is not powerful enough to drive some video formats. (Media players interpret video very differently than video editors.)
Have you started a Premiere Elements project yet that uses this video's specs? This will often trigger Premiere Elements to download the necessary components for interpretting the video.
The videos I use are created with different devices.
I have HD videos taken with a Pentax DSLR and I have Full-HD videos taken with a Windows Phone 8 device.
Both playback on my Laptop without any stottering with different software. I checked WMP and VLC. Even when using my Laptop with energy-saving profile these videos can be played without stottering.
When I playback the videos in PSE11 Organizer I don't want to edit them - just playback. So why should the internal player behave different? I agree with you - this might be different when I playback the videos in Premiere Elements 11 (as this is a video editing software). But when using Photoshop Elements 11 I want to be able to playback videos in the same performance as I can do with WMP or VLC. If Photoshop Elements 11 can't do that - why? The organizer of PSE11 is not an editor. It should be able to playback videos the same way (with the same performance) as other players on my laptop.
Can you please explain this sentence: "Have you started a Premiere Elements project yet that uses this video's specs? This will often trigger Premiere Elements to download the necessary components for interpretting the video." Is there anything I can do to improve video playback performance?
As Steve said, simple playback in other software is NOT the same as playing inside editing software... even for playback, editing software just is not like simple playback software
The Tutorial Links Page http://forums.adobe.com/thread/1275830 has links about starting new projects
But... for DSLR and "maybe" for your cell phone... you need an i7 and two fast hard drives for smooth editing... drive 1 for Windows and all programs, drive 2 for video files... both drives 7200 RPM
And have you started a Premiere Elements project yet for each of these video formats by placing a sample of each clip at the beginning of your timeline?
You need to do this in order for the program to download and install the necessary components for editing this video.
You also need to have the latest version of Quicktime, per the program's requirements.