Na I dont like to use Javascript unless I really have to for the reason you just pointed out that 10% of users have javascript turned off, also most of the things it does tend to be tacky too. But saying that it does have its uses sometimes.
Importance of it not very much at all, XHTML and CSS to a high standard and then a server-side language are the most important in my opinion.
Once you have some programming experiance it makes it easyer to pickup other languages anyways, so once you have got your server side language sorted you could soon work on javascript a bit and should pick it up fairly easy.
