Laptop problems

alright, this is kind of a two in one question...alrighti just got this emachine like two days ago, and wasnt really expecting any problems with it, but like 20 mins ago, I was listening to music, and the song started to skip, and I went to close itunes,...

and my mouse icon thing started to move all over the screen, and then everything froze, and the screen went black, but the song was still playing, and skippin... I had to take out the battery because the power button wouldnt even work. its working fine now, but I want to know if its a common problem, or if I should return it or something... and the other question is, my built in webcam wont work on the laptop either... is there something I need to download for it?

Might be that you don't have enough memory in there, or the processor is too slow, or perhaps too many other programs are running at the same time?