PS2 & XBOX SNKP PORTS ??????????

Why is it that all playmore ps2 japan ports such as metal slug 4 & 5 on ps2 and svc chaos for xbox have black lines on the side of the tv screen, or a minimized display???? The neo is full screen!!!!!! I was wondering if anyone knew or if anyone else was annoyed by this!!!!! Let Me Know.......

it happens with PSX games on the PS2 aswell, some not all but happend with my KOF99 PSX.

now for those MS 4,5 i have.
i tihnk its just that maybe if they stretched the image when its on ps2, maybe it makes it look bad?
anyway if you dont like it go and buy an MVS or AES system and buy MS 4,5 and play them without those black lines.