We brought our 3 year old twins to Paris and we stayed at this very hotel - the Holiday Inn Paris Republique in 2007. We chose the hotel because it is very close to the Metro, with five lines going through it -- so you can go anywhere! But we decided to take the taxi to the hotel because it was quicker and we had our carseats anyway. It cost about 45 Euros. But, you can also take the train for about 8 Euro per person. You can take RER from Terminal 3 Charles de Gaulle airport to Gare du Nord (8 Euro) then Metro to Republique (100 metres from hotel). It is so easy to find! Good Luck!
Also, the price of our hotel was very reasonable compared to others and breakfast was included which was very good buffet - but if not included in your room price I think it costs over 20 Euros. Also, the room given to us was big with slanted roofs and if you stick your neck out the window, you can see the twinkling Eiffel. The twins had adequate space for playing... We were mostly using the Metro and just arrived at the hotel tired and slept...check in was easy. When we have bought a lot of stuff, we just leave it at the hotel and then go out again! It was fun! Hope this helps you...
100 meters to Metro and buffet breakfast was good (better if included in price of your room because otherwise you are charged over 20 Euro)
