Is there a way to create a virtual machine with Linux?
Where do I get Linux?
Is there any tutorial for newbies to learn about the basics of how to use?
Is there any programming language for Linux?
If Orbiter moves to Linux some day, I would like to keep having stuff that people can use.
To give an overview, Linux is a OS kernel from UNIX class. All microsoft PC operating systems (OS) share similar design and commands, similarly, all UNIX class OS share their own basic design.
"Linux" is commonly used as a name of the system, but it is only the kernel - a main part of OS. Unlike Windows series, Linux does not come in few pre-packed products (Win 98, Win XP, ...), and can be assembled out of different set of programs and components by advanced users. For newbies and common users there are many pre-composed distributions, like Ubuntu computerex given a link to.
To learn the basics, just look for some "Linux for dummies" kind of book, or sites like
http://www.linux-tutorial.info .
Linux is an open-source system. The kernel is written in C and the applications are written in either C or C++. The C and C++ compiler, GCC (GNU C Compiler, lately GNU Compiler Collection), is available in any serious distribution. Other languages can be used too, but C is the preferable one, as the whole is written and designed for it. I haven't heared about visual basic compiler for it, but it could exist.
Programs are not made in programming languages, they are made using programming languages. So, it will be a good idea for you to get used to a better tool than visual basic, especially if you are going to write programs for Linux.
As the virtual machines are concerned, VMWare player is as good a choice as Qemu, first is semi-commercial, second is free and OSS. What to download on virtual appliance page depends on what do you need a virtual machine for.
EDIT: Looking closely i think you meant a virtual machine with Linux in it under Windows?
Then
http://www.vmware.com/appliances/directory/1224 (VMWare player appliance) or similar to it should fit your need.