I'm not sure how you get specific Kareoke videos up on the TV without a laptop. It is by FAR the best way to get video out to the TV with specific music/songs.
By placing the SWM15 in next to your AV receiver, then connecting the HDMI OUT to your AV receiver, you will get a permanent installed device which you can connect any laptop to at any time easily, and disconnect it when you don't need the laptop there.
The laptop video will pass through the system and appear on your TV. So, you can hook up the laptop, use a wireless keyboard and mouse, and run the entire show from the TV. I'm a 50+ year old at this point who needs glasses, so I feel your pain on working off a laptop screen (though it is part of my job).
LAPTOP->HDMI->SWM15->HDMI->AV RECEIVER->HDMI->TV (and room speakers)
Video will appear on your TV.
Audio will come out of your room's speakers.
I recently recommended this to a friend, but he hasn't gotten it yet, so I can't speak to the quality. This is truly what makes so much sense to me to use. And keep it simple.