This looks like you used the pseudo-vector tools in fireworks, am I right? Grab illustrator, and your lines will look better.
You should probably just grab
inkscape instead because it's free, except if you feel like paying $200 even with the student discount in which case Illustrator is a great choice.
Unless you plan on getting illustrator without paying for it, in which case, shame on you for stealing from a huge corporation that makes millions of dollars every year. Inkscape will probably download a lot faster and you don't have to worry about any viruses, I've been using it for over a year now and love it and use it for basically everything that requires drawing.