Can I use PC speakers with my TV set?
Headphones have very small power requirements.
If your PC speakers are not the powered kind, then the volume is going to be very low.
You'll be better off just using the TV internal speaker.
If your PC speakers are powered then, which jack you use might depend on how you want to manage volume control.
Audio out is fixed level and usually better sound thru an amp, while headphone jack is controlled by TV volume.
You can get adapters for either connection.