When you go to Settings-General-About and scroll to Model does the string look like this: "M......LL/A"?
If so, then, press and hold the Power and Home buttons until the Apple logo appears. Otherwise post back with the actual string.
If that does not help, follow the steps below to complete activation on a CDMA network.
If you still cannot call or text, do a restore via iTunes.
After that there are two further things to do:
1) contact Boost Mobile and request an account refresh to reprovision the device.
2) contact Apple Support for a hardware evaluation.