Reaction of magnesium with lead dioxide | 2Mg + PbO2 = 2MgO + Pb
Isolate lead from such a reaction can not even hope - it instantly evaporates due to the huge amount of heat released.
By the way, the mixture with lead dioxide becomes unstable - it reacts to friction and impact.
2Mg + 2PbO2 = 2MgO + Pb