Why is my Acer Aspire One D255 constantly freezing on me?

I've only had my Acer Aspire One D255 for less than three months and some odd weeks; and about two or three weeks ago, it's been freezing on me, in the middle of watching movies and listening to music, and when my computer freezes, it make this loud alarm noise. I tried the Ctrl+Alt+Del button and it doesn't work; I have to hold on to the power button to shut it off.