How do I transpose this music from what key to what?

For the play I'm in, I have to sing. I don't exactly have the whole
melody figured out. I found sheet music, but it's a tad too high.

http://sniff.numachi.com/pages/tiCOMEHOME;ttCOMEHOME.html

I managed to figure out some of the notes on virtualpiano.
Where it says "And no one to help her but me. Come home, come home,
come home. Please father, dear father, come home." The notes go:
YttYtYiY. ti, to, tO. Ytt, YtY, iY. (Virtual piano.)

Any help would be great. Thank you. :)