Yes
>Is Linux a real alternative to WinXP or other Windows versions for the home and/or small business user?
Yes is the straight answer.
If you trained someone from scratch on Linux, who had never used a PC before then they would be as productive, if not more as it's very secure and less targetted by malware, as a Windows user.
However if you have used Windows it is different. There are things to learn and things to unlearn. The key issues are dealing with all the propriatary files "business" uses and making the choice between all the optioons Linux and open source software offers.
In General, with a modern PC and Linux distribution inistallation is simple - especially if you get your internet connection via a router into the ethernet port.
My suggestion, make the break gently, install Open Office and try all the spread sheets and documents you have in that instead of MS Office. Switch browsers form IE to Firefox (Keep IE or doing any manual Windows updates becoems tedious!). Load Thunderbird instead of Outlook Express (I must admit I am so used to Outlook form the Office Thunderbird at home toook a bit more getting used to!)
Once you are comfortable with those core applications, which all look and work the same under Linux, the switch will be much smoother.
Memetic