Other than SecuROM, Batman shouldn't have affected anything.

You may just want to download another game that uses GFWL and uses that same set of keys as Halo 2. Pyong knows this part better than me, so you'll have to find him for that.

GFWL might just be fucked too. Right now the standalone client doesn't even work, and GFW hasn't come out with a fix yet (they know about it, at least).