Which game should I get? My sims or High School Musical: Sing it!

I've wanted a game where I can just sit down and enjoy. My Sims seems good for that. I like the graphics and it looks fun.

I've also wanted a game where I can sing. I love to sing, and I could do it all day long!

~So, what do you think I should get? Please tell me why and maybe a little persuasion? Thank you. <(^0^)>