I find that windows OS’s are specifically desighned for “the lamen user”, I think that they are well desighed and offer a plethora of features, I dont really like Windows Vista but XP is a strong OS in my opinion (and probably one or if not the most globally used), the Security of Windows is not really that strong “unless the user makes it so”, it does have a lot of patches over Win 2k but still not very secure…
I think that’s because it’s so widely used thus vulnerabilities are allways discovered, and also the standard Windows TCP/IP > UDP implementation via the firewall is also not very secure and doesn’t offer good user mod config settings for that sector. (I think one of the most secure comps out straight out of the box is probably novell, but thats a different matter).
Linux is probably one of my favourites and is constantly becoming more user freindly, rather than text based and typing things like: user/bin/passwd, ls, ect, it is one of the worlds most powerfull OS’s and thats because it’s part of the unix family, though… I would not suggest a first user to linux as it can get very complex at
times… it is in my opinion more secure than XP and win 2000 as their are not as many vulns ‘n’ exploits yet.
I dont have a great deal of knowledge on macs so i’d rather leave this part.
Hope i’ve helped