Because windows 8 themes are basically still windows 7 themes, they just have windows 8 graphics as the background colour. Thier coding is still the same.
If you mean "Visual Styles" by saying "Themes", the extensions of windows 7 and windows 8 visual styles are different. That makes it almost impossible to install windows 7 visual styles on windows 8. There may be other alternatives for it.
Yes, most of them will work.
In general, yes; most software that runs under windows 7 will run under windows 8.
Windows 8 Only
will internet explorer 6, 7, or 8 run on windows 8
No windows will work on PS3. The Windows 7 is an operating system developed by Microsoft and the PS3 does not run Windows in any form of the operating system from Windows 95 to Windows 8
The only operating systems that run "SimCity Societies" include: Windows Vista Home Edition, Windows Vista Professional, Windows Vista Media Center Edition, Windows 7 Home Premium, Windows 7 Home Edition, Windows 7 Professional, Windows 7 Ultimate, Windows 8 Home Edition, Windows 8 Home Premium, Windows 8 Professional, Windows & Ultimate, and last but not least the: Mac OS X Snow Leopard.
You can run Windows 7 with 1-2 GB of RAM depending on what you are doing. (More stuff you need more RAM) I Would go with at least 4 if not 8 GB of RAM to run Windows 7.
There are many versions of Windows available for laptops today. Most laptops run on the latest versions of Windows (currently Windows 8). Many laptops also run on Windows 7.
There's no reason why it shouldn't run on Windows 8.
I believe so.
Any game designed to run on DirectX 11 or higher will run on Windows 8, as well as native Windows 8 apps. Games that are designed to run in, for example, XP or lower, may not run correctly in Windows 8.