Forum Moderators: mack
What you are asking is a difficult to answer. There is so much more to speed than your choice of technology or coding language. It depends not only on what you want to acheive and the sort of site you are building, but how the code is used, the quality of the coding, the speed of the server and a myriad of other things.
There really is no "this one is best" answer possible.
For client-side coding, I prefer to use XHTML 1.0 strict in collaboration with CSS2. If you're talking loading speed, you're talking CSS ;)
You have three areas of concern:
1. the time it takes requests to wend their way from a user to you and the time it takes the reply to gte back. That is mainly out of your control (you can't control where the user connects from) but you can ensure your ISP is not connected to the nearest fat pipe by a long and over-congested route.
2. the time spent in the server up to the point that you emit the </html> tag. That depends on many factors including how much else is running on the server; its raw power; size of memory cache and working set; time to load langauge interpretor vs overheads of FastCGI; etc etc.
3. the time it takes your pages to render. This is partially out of your control -- some people will be using natuarlly slow browsers on antique computers. But not entirely. Keep your images small, use few tables (some browsers wait for the </table> tag before starting to render); how much Javascript you make the browser run; etc, etc.
Programming language is a tiny aspect of that.
I picked my language because it allows me to do innovative things. Other people pick "industry standard" languages because it is easy to bolt standard components together.
Choice of language is a highly subjective issue too: like naming the "best" restaurant in town without first qualifying the meaning of the word "best".