Question about Toshiba 40rv525u

[Adegan]

To the people that have Toshiba LCDs, what picture size do you use for Blu-ray viewing/PS3? Right now I use the Natural setting, but in the instructions it says that the Native setting is better for 1080p resolutions. But I find that in Native the black bars are too thick and occupy a lot of space, like watching a widescreen movie in a 4:3 tv. I find that Natural has a more correct widescreen presentation. I am worried that the picture is getting some type of overscan although it's not that noticeable.