Ive only played Star Ocean II and Till The End of Time and I enjoyed them for the most part, Most of teh problems I had were with Till The End Of Time. The beginning is painful, after that it gets pretty good, but I found it to be false advertised. It promised a Cool Sci Fi feel, but all of Disc 1 was in a medievil setting, and for the larger part of Disc 2 it was more medi, duno if thats bad to others but I was looking for a change at the time. Battles are fast and fun and make you more active but I found that you could simpley get through them with button bashing.
ST 2 was better in my eyes in almost everyway, get that first and if you like it get Star Ocean 3
Im not sure about ST1 But I can imagine that it would be good.