Just as audio CDs and CD players have given way mp3 files and digital players so goes the karaoke disc and their players. Computer based karaoke systems are the future of karaoke and for many good reasons. CDG karaoke discs have always been a nuisance to transport, store, handle, and maintain. A karaoke host will seldom get through an entire performance without at least one instance of broken graphics or skipping because of a scratched, dirty, or defective disc. Home users will equally benefit from a computer based system.
Basically you are going to turn your laptop into a karaoke player and your CDG discs into karaoke song files. The major difference between a karaoke laptop for professional use and one for home use is the software used. The home user who will primarily use the laptop for small parties, practicing songs, and making recordings of themselves, would typically go with a program like Siglos Karaoke Player/Recorder. Professionals will need "hosting" software that has features like song database creation, song search, singer history, singer rotation, remote monitor support, etc..
Connecting to some TVs may be a bit more of a challenge. My favorite work-around is to convert the video signal to VHF and use coaxial cable which is supported by virtually all TVs. If the laptop has s-video out you would simply use an RF modulatorr to convert the signal. If there is no s-video output you will need to convert the VGA to s-video and then the s-video to VHF with the RF modulator.
A full featured hosting program that has the distinction of being the only one that offers the Karaoke Cloud subscription service integration. This allows you to have a large library of karaoke songs without a huge initial investment.
Siglos Karaoke Professional
Another full featured hosting application that has the added ability to play CDG discs from a computers CD/DVD drive.
Video Hoster with Song Book Creator
The only fully integrated hosting application which means it includes a disc ripping feature, a song book creation and printing feature, and every show hosting feature you could ever want.