I've been using ClassicShell ever since I started with Windows 8, and while it is an improvement for controls in the desktop over the default, it has also had some frustrating little glitches. The most noticeable one is the delay in opening the list of programs.
So I've been trying another alternative, and this one is about as close to the Windows 7 start as you will find. So far, I have no complaints about it. Like most of the start replacements, this one can be configured to fit your specific needs. You can, of course, skip the new GUI Start screen and go straight into the desktop. And you can eliminate the corner and edge controls so they don't annoy you to death while working in the desktop. I've left the top right corner hotspot active so I have a quick way into the Charms bar if I need it.
It lacks the list of apps in the new GUI that ClassicShell offered, but I never used this anyway, so not a great loss for me.
If you are interested, there is a 30 day trial available. After that you'd need to purchase the program for $3. And you get a license that is good for two computers.
You can find it here: http://www.startisback.com/