You wont get the classic start menu back yet. You do have a shutdown feature bottom left if you right click. All the other programs the easiest thing I've found to do is just start typing anywhere on the tiles screen and it will pop up the search box.
Also there is an option to boot right to desktop now. Personally I just added all my desktop icons to the tiles page trying to get everything in one place.
1. After booting Windows 8.1 (here's how to get the preview if you don't already have it), click the Desktop tile to enter Desktop mode.
2. Right-click any open area in the taskbar, then click Properties.
3. Click the Navigation tab, then check the box next to Go to the desktop instead of Start when I sign in.
4. Click OK, then reboot. Windows should plunk you right into Desktop.