To solve this expression, we need to follow the order of operations (PEMDAS/BODMAS).

First, let's simplify the exponent: (25:5)^3 = 5^3 = 125.

Next, we'll simplify the expression inside the brackets: 125 - 5^2 = 125 - 25 = 100.

Now, we can substitute the simplified expression back into the original expression: 123 + 23 * 100.

Next, we'll perform the multiplication: 23 * 100 = 2300.

Finally, we'll perform the addition: 123 + 2300 = 2423.

Therefore, 123 + 23 * [(25:5)^3 - 5^2] equals 2423.