But in 8.1, you need never even see the Start Screen, and you don't need 3rd-party stuff to do it. Simply right-click on the task-bar then go to Properties>Navigation. There, you can customise how Win 8.1 starts, and what it starts to. See pic 1 below.
The All Apps screen can be accessed directly now, without having to go through the Start Screen. All Apps is still somewhat shambolic, but new customising options do help. With a few more options (like being able to hide and move tiles more easily), it could become a viable Start menu. The potential is there. See pic 2 below.
There are at least two ways to get a replacement (of sorts) for the Win 7 Start menu without resorting to 3rd-party programs like Classic Shell or StartIsBack. Firstly, there's the old and all-but-forgotten Quick-Launch tool bar.
Enable Quick-Launch toolbar by first unlocking the taskbar. Then right-click on the task-bar and go Toolbars>New Toolbar. Then drill down to C:\Users\Username\AppData\Roaming\Microsoft\Internet Explorer. Highlight, but do not open, the Quick Launch Folder, then click on OK. Go back to the task-bar, and you'll see it is enabled. Configure it by moving the two vertical bars, then re-lock the task-bar. Done! See pic 3 below.
There's also a version of the old 'Win 95/98/XP classic' Start menu cleverly hidden in 8 and 8.1 as well. I used it on the Win 8 DP before I discovered 3rd-party fixes, and it works reasonably well.
Enable 'Classic' Start Menu by following Jimbo's tutorial here... More Than 3 Out of 4 Enthusiasts Reject Windows 8 - Page 18 - Windows 7 Support Forums See pic 4 below.
All screenshots taken from Windows 8.1 preview.