Movies/Videos LAGS, GLITCHES, and is CHOPPY!!

I have a MacBook, 2007, mini dvi port, upgraded RAM to 4GB.

I've been having issues with video playback. For instance I typically use VLC player for all my video watching and when I connect my mac using mini dvi adapter to hdmi, I get picture lagging, glitching, and choppy video...

Here is a picture of one of the problems, the glitch:



The lag or chopping is when the picture seems to freeze momentarily and the audio continues and then the pics starts to move again for a short period of time and then freezes again...this keeps happening repeatedly.

I have a brand new ASUS LCD HD Widescreen Monitor (http://www.newegg.com/Product/Product.aspx?Item=N82E16824236049)

Yet all this stuff is happening. In addition to this monitor, my roommates and I have a 50 inch Samsung in our living room and this happens on that screen too!

I'm pretty sure it cannot be the video file because then every single video file i've downloaded recently is corrupt or something..

Is it the video file(s), my computer, the screen(s), the cable connecting mac to screen(s)? ahhhhhhhhhhhhhh this is killing me mad:

So with no idea how to go about troubleshooting this or canceling out the dead end thoughts im beginning to think its my computer. Is that that possible? What can be causing this, and does anyone have any ideas for me?

Please please give me some suggestions towards a fix!

Thanks,

Steve

Well is it choppy on your macbook screen itself with no external? if it works fine on your mb screen i would start with replacing cables personaly.

it will sometimes. i've always used VLC, someone suggested Movist, which i have been testing and its okay, got rid of the glitching but not lag. any ideas on how to troubleshoot this?