Blu-ray playback choppy, sound doesn't work

[ro44]

I'm having trouble playing Blu-rays on my tv through my HP laptop. The picture is choppy and sound doesn't work. I have my laptop connected through HDMI and the picture is fine, its just Blu-rays that don't work.
Do I need to change the refresh rate on my computer?
My tv is an LG plasma 42PG20-UA and Windows7 on my comp.

Thanks for your help,

 

[Tmagic650]

"Do I need to change the refresh rate on my computer?"...

I would say yes. Adjust the setting up a little from 60 Hz

 

[ro44]

How do I do that?
Is it under "Display" on Control Panel?

 

[Tmagic650]

Under Display in the Control Panel

 

[Ultiweap]

Or simply do:

Right click on desktop--->screen resolution-->advanced setting-->select monitor-->and change the Hertz