Yes, given the present scenario, a war with China is in India's national interest because India has the chances to win the war right now. It may not be possible for India to win a war against China in the future. The wind is one India's side.
BTW, if China gives Tibet to India, India will not need to go for war. I have the strong believe that Chinese leaders will do that. The Chinese leaders will give up Tibet and the Chinese will then start rationalizing the separation of Tibet from China because Chinese know that whatever their leaders do is for the good of China and they cannot question any move their authoritarian Govt takes.
If the Chinese Govt declares that Tibet is no longer with China, you won't have the guts to protest against your Govt because then your will be run over by a tank sent by your mighty PLA.