Thrust me,Linux is something you are looking for if you wanna start programming the best way.There are so many languages you can write your programs in like Python,Perl,C,C++,Java etc.and if you don't know how it wan't be a problem to learn since you have expirience in programing.Take a look at this site to learn some basics about Linux bash shell programming http://www.arachnoid.com/linux/shell_programming.html
.For Web development see http://www.rubyonrails.org/
and there are so many apps that can help you with that like Nvu,KompoZer etc.
Every Linux distro comes with everything you need to start programming,and if you want something else,you just download it from the repos,and there are so many people that will help you,and then you will see what open source is all about and what you have been missing.
Install Linux as soon as you can.
And yes you can have ASP.NET on Linux,take a look at this http://aspalliance.com/387