Do you mean those metal thingies that are labeled t1 / t2 and 1 /2? To my eye they seem to be sort of transformers, and those red ones, yeah, probadly varistors, but hard to say without any markings.
As for testing them, transformers either short inside or snap cut (so short circuit or open circuit) and hard to test without knowing values they were made. Varistors fail rarely in my understanding, they work when needed for protection. Others please correct me, but at least if they show short circuit with multimeter, they're toast, but at least they look ok to me.
edit. saw you mentioned about varistor markings, my bad
150/4 sounds like capacitor marking more, but no idea what that 4 means, or 150 in this matter....