I have not played the remake, but 3 is great. Dealt with a lot of interesting themes like death and change. 4 thematically really fits the high school setting, because it's all about accepting the uncomfortable parts of yourself and growing up. 5 thematically is shit lol. But it's the most streamlined in gameplay so it's got that going for it.
Someday I will play the earlier ones, I hear they are very good.