Sure, it\'s easy. Just not with the particular stereo you\'re looking at. If you look on the back of your PS2 you\'ll see a small hole that has a flap over it near the bottom (if it\'s standing vertical) or left end(if it\'s sitting horizontal). That\'s a connection for a fiber optic line.
If you check the "technical details" of that system you\'re looking at, you\'ll see it doesn\'t support "Optical Digital Input". Also to get 5.1 surround you\'ll need a stereo that also supports "Dolby Digital 5.1 Decoding".
Usually a stereo has these 2 attributes together. Just make sure whatever you get supports Optical Digital Input and you\'ll be fine.