2 AA cells in series will start at around 3V but the voltage will steadily drop as the cells discharge and they are not considered totally flat until they are down to 2V (1V per cell).Hobby project with 2 AA batteries
Porbably not. The LED was rated at 2.0V-2.2V. The current was not mentioned but most 5mm LEDs are rated at 20mA with 30mA as the maximum allowed current. Your current of 100mA will soon burn them out.A red led would work with about 10 ohms, green & other colours need higher voltages so if you can use a red.