My web programming experience consists of PHP, and a little bit of Ruby on Rails. For PHP, Netbeans is great. For RoR, I used Aptana Studio, which was nice as well.
Like jedishrfu said, C++ is rarely used in website design. Server-side code is usually written in scripting languages or Java (which is like a hybrid of a scripting and compiled language). I've used the Netbeans and the Code::Blocks IDEs for C++ programming; both are good. Code::Blocks is specifically designed for C++ development, but it was a little buggy the last time I used it.
With all that said, I think it's best for people just starting to learn programming to start programming without using an IDE first. A syntax highlighting text editor (Notepad++, Vim, Gedit, Kwrite, TextMate, etc) and a compiler with a command-line interface are sufficient (if you're using a compiled language like C++ or Java). IDEs start becoming more useful when working on larger projects.