I think it looks good now too. If you really want to make it not as wide just reduce the width on .main. It's set for 97% now. Try 60% maybe (just a guess). When you do it will move way over to the left so to center it again change the margin on .man from 5px to:
.main {margin:5px auto}
For rounded corners at the moment you need to use images. The need is because IE doesn't yet understand the CSS3 spec for border-radius. Until it does curves are going to be done by creating images and then adding them in the corners.
You can check out
Spiffy Corners to see one way to do it.
I'm still with John though in that it looks good as is. I'd leave it.