Final answer:
The artist known for the 1998 hit 'Frozen' which reached number 2 on the charts and featured the lyrics 'when your heart's not open', is Madonna.
Step-by-step explanation:
The artist who in 1998 was 'Frozen' at No. 2, a song associated with the lyrics "when your heart's not open," is a. Madonna. This track was part of her seventh studio album titled 'Ray of Light', which was a significant success of the late 1990s and showed Madonna's versatility and artistic growth. The song was known for its electronic influences and introspective lyrics, and it was highly regarded by critics and fans alike. Although it reached No. 2 on the Billboard Hot 100 chart, it nonetheless solidified Madonna's reputation as a pop music icon.