The lcd menu items are in the ultralcd.cpp file. To remove the FLOW and FLOW0 items just comment out these lines:
MENU_ITEM_EDIT(int3, MSG_FLOW, &extrudemultiply, 10, 999);
MENU_ITEM_EDIT(int3, MSG_FLOW0, &extruder_multiply[0], 10, 999);
The temperature control options are in the function
lcd_control_temperature_menu