Best Web Design Language in your opinion?

Depends on ur task , Python, Perl, , PHP, and Java would be dominants and are free too ! Each has its own advantage : Python has cleaner code, easier to read and maintain ;Perl is much older and so much code in it ;PHP is widely used too

None of the languages you specified are web design languages. You can use them to generate dynamic websites, but the websites themselves will still be written in HTML, xHTML, WML etc.

But to your question I'd go with PHP. Why, its what I work with.

But besides that its the easiest of the three to get into, Java though still the most widespread of the three (the .NET framework is the forth you are thinking off) is too bloated and is beginning to loose popularity, though its support for writing web based, cross OS desktop based and mobile based applications is still useful.

PHP, especially PHP5 is extremely powerful in the write hands. Unfortunately the percentage of high quality developers is not very high due to its easy access. You can, of course, also write desktop aps with PHP using PHP GTK if you really wish to (why would you though).

Ruby is still pretty new and finding its feet. Its a framework really, and its reliance of the bloated prototype JS library for its AJAX support is something that it will regret in the future. At the moment this is a popular "language to learn" for development professionals as its quiet "in" with non-technical management teams.

It really depends on what you're doing. XHTML is probably one of the most important languages for web design. And CSS is pretty high up there was well. .NET would be pretty good if you're considering Java. But again, it all depends on what you're doing. For instance, if you want a database, SQL would make sense to use.

CSS + XHTML