Just don't play SimCity 2013. (My personal opinion). I loved SimCity, but the reboot was just atrocious.
Anyways, with a 240, you won't be able to play it at high. The recommended level of cards for SimCity on high are around the GTS 450 - GTX 275 range. Medium would be more around the playable range, I'd think.
Starcraft would be about the same.