they are both good builds.
the AMD chip that vernong suggested should run cooler and consume less power than the celeron that puddle jumper suggests.
personally, i think the hd3200 (AMD) is a MUCH better onboard graphics solution.
that celery processor may use the same architecture as a c2d, but it's lack of cache severely cripples it IMO. then again, it's only 60 bucks. cant argue with that.
i'd do the AMD build, but that's what i do. you've got AMD in your name, lol...so support them or don't.
either of the above will work well for your sister.