I have programmed client/server apps using Windows Presentation Foundation (WPF), C# for code and code behind, T-SQL on MS SQL for some pretty big clients.

I would like to program similar things for the linux desktop.
Although I think there may be better (more productive/faster to code correctly) languages than C++, I am not totally discounting C++ either.

1. So for starters I would need a graphical interface (IDE) to program. Eclipse / Code::Blocks or something.

2. I would need the appropriate language / framework to learn and implement code to achieve my goals, C++, Python, Java / GTK, QT, more?

3. I would need server distro options. Cent-OS, RedHat ect.

4. I would need a database option. MySql, MariaDB, etc.

So to restate the question:
What is the best framework(s) for making graphical desktop client / server apps?

I am looking forward to recommendations!!!

Well... I don't have direct experience with most of those options you listed, but I'm pretty sure the answer is 'whichever you prefer' because AFAIK they all meet your requirements.

Python 3.x + PyQt4 for the gui + database of choice (PostgreSQL, etc.) + PyCharm 3.x Community edition (very good code intelligence and support for PyQt4) would be one option/example.

You could sub wxpython for the gui library (have to change to python 2.x), mysql or mariadb for the database, or any of a dozen editors/IDEs as needed.

Again, pretty much any of the options you listed should work. 'Best' is highly subjective... whatever tickles your fancy.

Qt (both Python and C++ are good for Qt programming) has SQL support right in its standard library. http://qt-project.org/doc/qt-4.8/qtsql.html

Qt is very programmer-friendly.