As with all PCs, what other software is supplied is entirely down to the PC supplier, but it is very rare to see a machine these days which comes with anything but the bare minimum.
You need to check the specific offer details. Of course, most applications that you already own can be installed on a new PC.
Just as an aside, before purchasing a machine running Vista, you might want to type "Vista" into the AB search box on the left, and check what other ABers are saying about it. Personally, I would rather get a virus :-)