Burning a CD. Assistance?

Hello,

When I put in a blank CD-R to burn music off of my Window's Media, options for what to do pop up as they always do. I click 'Burn an auido CD' and it registers onto my Burn List on Media Player at the top where it gives you remaining space. Though I have several songs on my list, it says that there are only three seconds taken up, but none of the bar is filled up. And when I go to the bottom to click 'Start Burn', the button is transparent and it won't let me click on it. My computer hasnt ever done this to me before and I've made plenty of Cd's, but now it's not deciding to work. I need this CD put together by tomorrow, but I'll find an alternate solution for now, but if you could get back to me before September 24th, it would really help. Thank you!