Which programming languages are multi-platform, fast, and object-oriented with non-limiting low-level os access? [on hold]

Which programming languages are multi-platform, fast, and object-oriented
with non-limiting low-level os access? [on hold]

I've been a web developer for a few years, and I want to get into desktop
program development. I'm looking for a language that will allow me to
write programs which are:
Multi-platform, supporting Windows, Mac, and Linux, either by default or
with little work.
Create programs which are fast.
Is object oriented.
Doesn't have any limitations in terms of what sort of programs can be
built with it (e.g, can be used to access lower level operating system
functions, e.g showing an icon in the taskbar or rebooting the computer)
(Bonus but not necessary) Has some tool for GUI creation
(Bonus but not necessary) Comes by default with tools for database access
such as with MySQL or SQLite
I'm on Linux, and would prefer not to use C# as there's no good IDE for it
available on Linux. However if its the best choice, I may be convinced to
switch for it.
Thanks in advance.