Yep, the new sets will be perfect. One is a dip your toe set, with just two mechs, at a low price point, with introductory rules. The larger one bumps up to eight mechs, which is more then plenty for any starting player.
There are low cost plastic lance packs out there to expand with. and after those intro sets, you'll want the Battletech manual. It is a mech only rulebook, with all the gun things mechs can do. Unlike the more comprehensive Total Warfare, its is mech centric, and has taken advanatge of time to be formatted in a way much better for newer players. Both sets have a couple of maps. There is a great section on 'things people usually get wrong about the rules' which will save a lot of time for new players, and has even surprised a few veteran players.
Link explaining it
http://bg.battletech.com/news/battlemech-manual-final-release/The manual is out in the world right now. You could get yourself a Christmas present by picking it up in preparation. For more varied terrain, there are the hexpacks, and you can still find collections of the old paper hex map packs out there in the wild.
Theres also a joyful option called Alpha strike, that your kid might like even better. Its a fast playing, minatures based version of Battletech. It feels like battletech, but moves so much faster. Mechs are redueced to a simple lien of stats contained on a card the size of a normma playing card. Attacks are resolved with one roll, and you can play a company sized game to completion as fast (or faster) than many lance sized games of battletech.
You can read about that here:
http://bg.battletech.com/test/alpha-strike/5160-2/If you get that, get the Companion as well which adds essential official rules changes, and a spectrum of options.
good luck with bringing your kid into the game!
