iTunes upgrade questions

[Lee]

I don't buy videos very often, but when I just went to buy one, the iTunes store wouldn't let me. It said that I have to upgrade to 7.0 or greater. I don't have any trouble buying music with my 6.0 version. I'm scared that if I upgrade, I'm going to lose everything in my library & it'll cause all kinds of problems with my computer. So my questions are: Has anyone here upgraded to a higher version of iTunes, & did you have any problems?

Thanks.

Lee