There used to be the time when saying "DREAMS" and "Hoshi wo Mezashite" was enough :) I'm afraid the only thing that can help me answer this now is naming the songs I like the least:
"Arigatou Ima", "Shissou Friday Night", "Game of Love", "Koi Yake", "Yawarakana mama de", "Lady Spider", "Rainbow", "Taiyou no Namida", "Sweet Martini" and "whisper"