that link only applies to old chipsets though. while they are still based on that kind of logic, the technology is far more advanced and will give you a more varied result in FSB/chipset differences. i see what you mean though...that is the basic logic of FSB/Chipset similarity. I guess if he didn't know that then it would have cleared up a few things...
Via will run fine for stock and even mild overclocks with an XP system. If you are looking for higher overclocks (which you are not) NF2 would be the way to go. I think you made a smart choice if you weren't planning on high overclocks, and trying to save cash (although an Abit NF7-S is only like $80)