Hello,
To answer your questions:
1) Linux has a GUI environment called X-Windows that runs with Linux. You can choose to be pure text mode (likely for servers), or GUI for desktops. You can get into the text mode from the graphical one.
2) Linux is similar in the look and feel.... similar like the various flavors of English. Linux is very different from Windoze in the software distrobution category, user philosophies, and virus defenses.
3) Linux can connect to the internet. Dunno if voice with YM works or not. I have streamed audio over the internet, so I know that works.
4) Linux has USB yes.
5) Games are all over the place. If you are looking for the latest WarCraft or big-name games, probably not, but I can play chess on Linux quite well. There is a port of Civilization out there for linux, or you can try emulation. Linux is not intended to be your Atari / Xbox / Gameboy replacement.
6) You can use a CD burner. Depends if the hardware you have is supported or not.
7) I like Fedora and SuSE. Others may like other distrobutions.
8) It is not usually necessary to purchase linux, but you may certainly financially support the authors of the code. You might have to purchase a support contract if you expect to call them and talk to them on your various issues.
Christian