Yes, it's called Windows XP
There isn't any Windows 7.8, but if you were referring to Windows Phone 7.8, it cannot be updated to Windows Phone 8 (note that I did not say Windows 8 because Windows 8 is for laptops, desktops and some tablets).
yes
Not very much because they made to be different, because windows vista wasn't all that good. Some things they do have in common are, they both have windows aero. Updated start menu, updated utilities.
2003 Windows is to old of an operating system and needs to be updated.
I don't know, you tell me...
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Windows 95 is 17 years old and windows 98 is 14 years old. this answer will get updated every couple of years.
Auto cad is not updated yet to work in Windows 7, go for Windows XP.
You do not have to upgrade to Windows 8 at all, but some people perfer to be updated with the latest softwares.
The newest and final form of Windows XP is Windows XP Service Pack 3. As of 2013, the OS will no longer be updated or upgraded.
The original RSync for Windows was launched in February 2000. A new updated version with extra features was launched in 2003 with the Windows Vista release.
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