Hi, i dont own a ps2 so im 100% sure, but i believe that unmodded a ps2 can only play DVD. Your best bet is to buy a mod chip or search the ps2 forums for a definate answer. Hope this helps.
I leant a friend with a PS2 some vcds and they wouldnt play in his, could have benn his version i suppose.
I have a newer version of the PS2 (SCPH39001 - about a year old) and I also have a mod chip in it (I believe it's the Magic 3) and it won't play vcd's or svcd's. That leads me to believe that it can't be done or it has to be in a special format or needs special code. Come to think of it, I believe I have seen some programs floating around that say they can make a ps2 bootable vcd. I'm not sure what it's called though.
I've tried play a VCD& SVCD backup on a PS2= won't play. I did get a dvd+r to play just fine so maybe you need to burn the VCD to dvd+r m8. Shoey