jtara - 4:35 pm on Nov 11, 2007 (gmt 0)

You won't be able to run your current programs that are installed on Vista under XP.

First of all, some of them might be written for Vista, or in any case were installed under Vista, and so might have incompatible DLLs, etc.

Further, there's the little matter of the registry. Almost all Windows programs require the registry to function, and, unfortunately, they need the registry they were installed under. That is, most large software packages will have installed critical entries into the registry of your Vista system. These will be unavailable on your XP system, and so the programs won't function.