Windows 8: want to use "traditional" desktop UI?

Windows 8 boots up with the tiled style UI, it was called "Metro", with each application displayed on the screen as a tile, you can put a lot of tiles on the screen as long as you feel comfortable and there is space for you to do it.

Since the first release of Windows 8 Preview, users are providing feedback about the UI and UX, and want to use the traditional desktop UI. To do it, it is as simple as just hitting one key on the keyboard of your PC, but to my own experience, I need to click the "Desktop" tile first in the "Metro" mode, which means the traditional desktop UI needs to be running on the CPU, then the click on the windows key on the PC's keyboard will switch me from Metro style to traditional style.
The other way to do it is to put your mouse at the lower left corner of the screen, then the icon of traditional desktop would show, and you can click it to switch. Or just put your mouse at the lower left corner, and do the left click on your mouse to switch back and forth between these 2 modes, this is the most easy way to do it.

After switching to the traditional desktop UI, you may find that there is not the "Star tup" button. Now in the social media, people are talking about Microsoft's latest decision to disable any 3rd party software capable of putting back the "Start up" button. One of the work around is to stick the app to the task bar.

Windows 8 provides similar functions of "Start up" button in other ways.
Please try to move your mouse to the lower right corner of the screen, which is near the end of the task bar, then a vertical menu would show up on the right side of the display, which has the options of "Search", "Share", "Start", "Devices" and "Settings". Putting mouse on the upper right corner of the screen would also work. I feel the motion event of the mouse is mimic the touch event on the screen, I think on tablet, user just need to touch the right corners of the display to show the menu.

In "Search", it would allow you to search the app you would like to you, and display a list of apps let you to choose. This feature provides quite the same function of "Start up" button which would list the apps when user clicks on it.

There seems to be no need to get the traditional "Start up" button back and put it at the lower left corner of the screen.

Users can also point the mouse to the left lower corner of the screen, then do the right click on the mouse, a menu would pop up and a list of options would be displayed there allowing user to choose.
User can choose "Search" to look for the apps. It would display quite the same screen mentioned above.

To get back to the desktop from the search screen, you just need to move the mouse to the upper left corner and click on the 'Desktop" icon, or try to move the mouse to the lower left corner again, and do the right click on your mouse, then from the menu, select "Desktop". Or simply put your mouse at the left lower corner, and do the left click on your mouse.