1.1. PROS: Jump Lists - see the files you've used recently by right-clicking on the icon on your taskbar. Simplifies device handlin. Devices appear as pictures of the device and also window can be minimized to the taskbar.
1.2. CONS: The Run menu is still gone from the Start menu, it was disabled by default in Vista. Also no more small icons for the taskbar. All the icons on the taskbar are large.
2. OS X
2.1. PROS: More than 90% of the desktop computers in the world run some sort of Windows operating system. Most widely supported operating system for games.
2.2. CONS: The most prone operating system for spyware and virus applications. Poor security and you are going to need support.
3. Ubuntu
3.1. PROS: It is completely free. You don't need expensive hardware to run it. Layout is clean, uncluttered and applications are easily accessible.
3.2. CONS: Firewall application is not included by default. Opera-alternative web browser. New users to Ubuntu need to need to install additional open source apps and utilities.
4. Chromium
4.1. PROS: All the sites performed are much faster. Open source. Big points for minimalistic approach. Allows plug-ins to run in their own process space. It won't crash. It gives you more control over tabs. It makes searching simpler. It opens new doors on your home page.
4.2. CONS: No mouse gestures. No synchronization. It's only in it's first Beta. You won't have any add- ons. You lose some history power.
5. Operating System Definition:
5.1. Software that controls the execution of computer programs and may provide various services.
