Forget Andronico's frozen-food section or Strawberry Canyon Pool. When the mercury soars, the best place to cool off really fast is Berkeley's Iceland. Lace up a pair of figure-skating or ice-hockey skates, hit the frozen stuff, and chill out big-time. Iceland takes you back to vintage skating rinks, to a time when life was innocent and nearly everyone was square. Get ready for a workout. There's hardly anybody there in summer, but come fall and winter, you'll be competing with the orthodontically challenged preteen set. College Nights have special discount admissions, and adults-only morning coffee sessions attract their share of regulars. Ice, baby.