Brahman , the all prevailing , the endless , the formless , the all-loving and merciful the seed soul of us all . And Brahma , Vishnu and Mahesh are just the names given by us to HIM performing his duties of creation (Brahma) , protection (Vishnu) and Destruction (Mahesh) as and when necessary .
While I was listening to Morari Bapus katha , he took a topic of whether Lord Rama was a human or Brahman (a question asked by mata Parvati to Mahadev) to which lord replies with the story of how the lord took human form for destruction of evil (Esp. Ravana) and said (in simple language) - I along with all the Devtas were worried about what to do with Ravana and then we approached Brahma , for he had given boons to Ravana , he too was helpless . Then we decided to approach Brahmana for solution of this trouble and as he is all prevailing we meditated upon him with love as He listens where love and selflessness is and ...... (Fast forwarding) Rama was born .
And as Rama (also Krsna) is Brahman himself and all the three god heads meditate upon him lord Shiva to serve him took form of Lord Hanumana .
This is the conclusion I have reached after reading upanishads and Gita (Vedas are too high level for me yet) . Also I have read on certain forums that in ancient times the three god heads were not worshiped (or were not there at all) and were created (either in reality or in names) for humans of kalyuga so as to help them worship God ("one who is subtler than subtle" as upanishads state).
Please answer my question dropping your natural inclinations , I too was inclined towards Lord Shiva and during that phase (few years back) refused to accept any other God being greater than Him .