On the programming level, everythins is new starting from the core and finishing with drivers and interface. Also, vista Aero Glass requires pixel shaders 2.0. Practically it's not better than windows xp.
No. Windows 7 is based upon Windows Vista but includes new features, bug fixes, and performance enhancements.
Yes. Look for ones that have a "Compatible with Windows Vista" logo on them. As of 2009, almost all new products are compatible with Windows Vista.
All new Taskbar
you can not degrade.. you have to do new installation
High Achievers Perfect Math Skills is compatible with Windows Vista.
Many new computers do not come with Windows Vista Basic. Some of the older ones do. You can request that they put Windows Vista basic on your computer upon purchasing.
on the internet
From what I can gather, Windows 7 improves on the security holes that were left in Vista as well as adding new graphics etc
DirectX 9 is included with Windows Vista.
There is no such thing as "Windows XP Vista." There is Windows XP and there is Windows Vista. They are two different versions of the Windows operating system (XP is older than Vista). As to which is better (XP or Vista) if that is your question -- I think most people would say that XP is better, but this probably depends on which operating system you are used to and what type of work you do with the computer. That said, even Windows Vista is out of date, now. New machines will have Windows 8 (or Windows 7 if it is slightly older).
EPS
That edition of Windows Vista does not exist. Windows Vista exists in two editions for home users: Windows Vista Home Basic and Windows Vista Home Premium.