Various aspects of burn of advanced fuel inertial fusion targets are discussed, including pure deuterium as well as D-3He targets. In the case of deuterium fuel, the mass of tritium and 3He created in D-D reactions is calculated as a function of the fuel R, keeping the fuel mass constant (20 mg). It has been found that as the fuel R is varied from 40 to 80 g/cm2, the burn of 3He increases from 20 to 75%, whereas 95% of the tritium is consumed during the burn. An ignition temperature of 5 keV is considered in these calculations. It has also been found that introduction of a small fraction of tritium atoms (1%) uniformly distributed in the deuterium fuel allows a reduction in ignition temperature by more than a factor of 2. In the case of D-3He targets, an ignition temperature of the order of 10 keV is required, but introducing 1% tritium atoms in the fuel allows an ignition temperature of 3 keV.