Depends on what kinda platform we are talking.
Server? Linux for sure.
Desktop? Windows
OFcourse I wouldn't even want Linux on my server I rather have freebsd.
To those who are saying Linux is more secure,let me ask you what distro you are using... Cause the only "secure" distros I have seen is debain stable and centos.
Any other one has huge flaws and exploits in them. For example ubuntu's sudo timeout leaves your system open for attack. As seen here -
http://www.youtube.com/watch?v=9HxFGQ8OpYw
Also note this does not only effect ubuntu it effects any distro with a sudo timeout.
Now ofcourse with that said I think we can all agree that any OS has flaws and exploits ... yes that also means you Amiga and haiku fans too
😛.
@ Black Angel I wouldn't install mandriva it has basically died. Almost all of the dev team has left. They are however making a new distro as seen here -http://mageia.org/en/ .With that said though,there is another great distro that was forked from mandriva called PClinuxOS and it is also a great distro. Or if you are willing to try any distro Opensuse has always been my best experience.