Hi
I'm not keen on the navigation gong over onto 2 lines - maybe reconsider how many top level options you have.
I think the header is quite nice, as already mentioned. Though I'd not use the animated gif, it makes the site look 'old'. Maybe more to do with the anti-aliasing on your text rather than the animation.
And yes, consider using normal images instead of flash. Even on my top of the range iMac it took too long to load, leaving me thinking there was a big blank space on your site for quite a few seconds (a long time in the world of the web)
Good effort though - keep refining and let us know how you go.
/Doug