Can some of you guys make a list of 5 to 10 essential PS1 games? Try not to make lists of 20 or 30 games... I can't afford it!!!

I just mean the best and most essential games. I've been buying some classics (Spyro, Crash, Tony Hawk 2, Tekken 3) and games I owned as a kid that maybe aren't classics (Rugrats Search for Reptar, Spongebob Squarepants Super Sponge, Armey Men 3D, Gameday 99) I'm looking for more stuff to play.