if you are going to use polys (and convert to sub-d's afterwards to get rounded edges) then make sure you add extra vertices (by spliting polygons) all the way around the edges, that way you will have slightly rounded edged and you won't lose the shape of the PS2. If you are only modelling the outside of the PS2, then use curves and loft them into a NURBS object if you are planning on having the disctray open, then use polys and create the disc tray seperate. to create the main body you could start from a basic poly cube and extrude all the grooves or you could texture the groves in (using a very clean-cut bump map, bear in mind though that this won't bump the edges). to make the disc tray again either loft some curves or start from a poly-cube (but instead of extruding (which can become very messy at times) why not try splitting (not subdividing) the polygon faces using the
edit polygons>split polygon tool
, if you do it right you'll find you'll have much more control over the final shape (and it can help with texturing because you will have made all the edges and know how they are arranged in the UV editor)