I trillionth the PS2 recommendations, and I suggest getting a DS second.
Xenoblade has absolutely nothing to do with Xenogears or Xenosaga btw. Not even in the slightest. Not even as a spiritual successor. They just tacked on the name to attract fans of the series and because the director wanted to put "Xeno" on something.
Well we still no nothing about the plot. Then again, Xenogears and Xenosaga are only loosely related plot-wise. I think it's fair to say that it's at least a spiritual successor.