The best Linux distro is really a matter of opinion/taste. You can see my opinion of the various distos here -
(Note that Debian has since released a new version).
You may want to consider Gentus (http://www.gentus.com), which is not mentioned in the aforementioned post. Gentus is actually put out by Abit, and from what I hear, if you have an Abit board Gentus in not a bad option. It actually installs a custom kernel depending on what board you have (it would also be the most likely to support the integrated sound). For full i815 support I THINK you will need either >2.2.17 or a 2.4.x kernel.