Tech support! and I need it ASAP! plse?

ok i need ur help! and fast if possible. I've searched high and low for the answer to my problem so now I'm bugging whom ever reads this to leave the hair that's left on my head.

I'd like to make a karoke video. I don't have the Cd for this song so I'm using another video of this song. I need to get the vocals off this video so it's just the song left. I can then make my karoke video. OK.

The problem: I only have the standard windows apps. like media player, movie maker, and a Realtek HD audio manager that I have. If you can help me then you get a smily and if you can then a pat on the back for at least reading this!
I also really  don't want to download any shady apps but if you know no other way then that is fine. just pleas help!

srry for my spelling I'm tired and want to be done with this today and srry for the legnthy speech.