how can I make a line like an HR in css which I can define his width, height and color?
you need to put something on the page, you could do a div with width height and color, apart from that i don't know. why do you need it?
HR is better then div ot it doesn't matter?
you can't set the color of hr (except IE)
So I guess I'll use DIV
The link posted also has a link to what I would consider a slightly outdated write up I did on the subject. You can also do a search here on "<hr> color" with threads that have me in them for even more info on this.