Microsoft is a company, and has existed in only one iteration since its founding.
All versions of Excel should work with all versions of Windows.
Yes.
All versions of Windows to-date have been made by Microsoft.
All versions of Microsoft Office (with the exception of those created for Macinthoshes) up to and including Office XP are compatible with Windows 98.
All versions of Windows to this day is created by Microsoft.
All versions of Windows to-date have been made by Microsoft.
Yes, all versions of Microsoft Office XP include Powerpoint.
I do not know of one of these however within Vista and on the Microsoft website you can compare versions of Vista.
Microsoft announced in March of 2009 that the Microsoft Encarta program would no longer be supported. The discontinuation included all disc and online versions.
You can download trial versions from the Microsoft website, but to get full versions you would have to buy them, by getting a version of Microsoft Office.
The default file name for all versions of Microsoft Excel is called "book1"
Microsoft Picture Manager is a program that is installed with all versions of the Microsoft Office suite. It is free, with purchase of any Office license.