m8 has changed his pc from windows to linux, reckons its better, smoother?? and less chance of getting bugs and viruses. is this true or not. is it worth changing over to this or staying with xp pro??
fingers on the buzzers and the answer is?? 
Don't believe the hype. This is one of the biggest problems with Linux. It is no less prone to bugs, and there are virii for Linux. There are loads more Windows virii, so all Windows users always run AV software. Linux users think they are immune, and don't bother. Pillocks.
wrt to smoothness/performance, Linux (along with any X11 based graphical system used on virtually every Unix) will be slow with graphical desktops. You have to understand the reasons for X11 to understand why it will never be as fast as Windows graphically. X11 was designed to be a multiuser networked system (basically, you'd run a graphical app via your own machine, but the app itself would run on a central Unix server). The layering needed for this destroys performance.
The one really, really good thing that Linux had was the Unix security model - every user ran with limited permission (same as running a 'Limited User' user account in XP, or 'User' in W2K). If you needed 'root' (Administrator in Windows) you had to temporarily switch to root user to perform that task. Trouble is, most distros have relaxed this now, and allow you to permenently run as root, which is every bit as dangerous as running as an Administrator in W2k/XP.
Vista has a great way around this elevated priviledge thing (knowing that most users consider not running as Admin is a comment about their penile performance) called UAC. Most stupid people turn this off because they are incredibly stupid and shouldn't be allowed near a computer. Leave it on. It kind of implements that part of the Unix security model whereby you're in a limited mode (thus can't do damage to machine), and your prompted to allow anything that needs higher rights. This can catch many nasties before you're machine is compromised (assuming you don't just answer 'Continue' without understand what and why something needs extra rights). Its not a complete answer - as per Unix/Linux, still possible to inject nasties via bugs - but its a massive improvement from the XP model, and every idiot running as Admin.
And don't get me started on Linux's resource (mis)management - its appalling.
Back to your original Q, there are plenty of free distros out there, try one, see what you think. Remember, most Windows apps won't run too well under Linux, those that will run tend to be slow. Also, be aware that Windows and Linux don't like each other much, so if you go dual boot, you need to know what you are doing.