I haven't done any serious programming in years. I went to Windows and really slacked off with learning stuff. I am interested in knowing which programming language(s) should I learn? I only know some HTML if you only include newer languages.
Well, there are a few directions from which to approach this. It all depends on what you want to do.
If you want to do some web-based stuff, like dynamic sites and such, pick up some PERL or PHP material. Both are quite capable and easy to pick up. If you can score a free web host with PHP or PERL support, that's a great place to learn. PHP is also fully-documented (http://www.php.net/), so you don't really need to get a book.
If you're into the light stuff, start with VB and work your way up. I wouldn't suggest toying with VB on your own, since it won't really teach you much technique. If you get some free course material or something, that'd be good.
If you want to get into intermediate or advanced programming, I suggest you start with compiled languages. Stuff like C/C++ or Java. If you haven't had a formal introduction to logic or you want to really understand its ties into programming, I'd say get some Assembly going, too. It's incredibly low-level, but you get a great feel for how things get done in a logical, step-by-step sense. Back onto the compiled stuff, C++ and Java are both object-oriented, and all are very powerful. Start off with console-based applications and, as you get more advanced, start off with simple graphical stuff. I supposed MFC is a good foundation for GUI programming with Windows. Java has some built-in GUI libraries IIRC. Personally, I would suggest you get a book or two and some online course material if possible.
A lot of the stuff I learned was through tinkering, but everything is based on the basic technique I learned in 101 classes. If you can get into a 101 programming course, you'll probably be pretty well off. Course material for that stuff is pretty easy to understand, too. If you can't, try to score some beginner textbooks. For me, the "Learn Blah in 2 Weeks" type books didn't really work too well, since I always zipped through the "boring" stuff. Find something that suits your reading/learning style.
I would really suggest learning a .NET language mainly because then it will be very easy to learn the other .NET languages.
Personally my learning in college has gone C -> C++ -> C# -> Java -> VB
C# is relatively new and is a mix between Java and C++ using purely .NET.
PHP is basically C programming between HTML tags.
I've heard VB is rather easy to learn, and it's a .NET language so that could be a good starting point.
I am personally of the opinion that Java is the easiest language to learn.
You can play around and get a feel for logic, and object oriented techniques without having to screw with memory management, etc.
I feel that if you go immediately to an Object-Oriented language like Java, it'll be harder to learn a functional language like C. That's speaking from experience watching students in my faculty learning Java first before C, and then needing to learn C in upper division courses.