Yes there are some differences in the Window and Ubunto operating systems , so it mainly depends on the needs and prefernces of the users to choose among these systems. For normal activities and surfing most people like the windows but I personally like the Ubunto because of its reliability and security features.
I don't actually use anti virus when I use Linux. Although I need windows for the programs that only work with them, I still come back to using Linux because I like it especially because I'm part of the developing team of an underdog distro back then.
Ubuntu is nice, but it isnt anymore secure than windows, the only difference is that windows is easier to make viruses for.
Not most. NO Windows executable will run in native Linux, and NO Linux executable will run in native Windows. Executables don't run in operating systems they weren't compiled (or assembled) for. That has absolutely nothing to do with whether one should be running Windows or Linux.
I have tried Ubuntu on my machine... it is a good OS but not for the user who uses his computer for entertainment like games, music, movies, chatting, video conferencing etc. Windows is more user friendly, the supporting applications are in millions I think... so I would prefer windows for home or simple office use...
http://winappleworld.com/should-you-consider-upgrading-to-windows-7-or-8-since-xp-support-is-ending-soon/ XP will be obsolete soon mate. And i personally prefer Mac or Linux as my mainstream Operating system. They are super safe and super awesome. Ubuntu comes third but you can always use Virtual machine.