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

First, let's simplify the exponents:
(-1/5)^2 = (-1/5) * (-1/5) = 1/25
(-1/2)^3 = (-1/2) * (-1/2) * (-1/2) = -1/8

Now, let's substitute these values back into the expression:
1/25 + 1/5 - 2 * (-1/8) - 1/2

Next, let's simplify the multiplication and addition/subtraction:
1/25 + 1/5 + 1/4 - 1/2

To add fractions, we need a common denominator. The least common multiple of 25, 5, 4, and 2 is 100. Let's convert all the fractions to have a denominator of 100:
(1/25) * (4/4) = 4/100
(1/5) * (20/20) = 20/100
(1/4) * (25/25) = 25/100
(1/2) * (50/50) = 50/100

Now, let's substitute these values back into the expression:
4/100 + 20/100 + 25/100 - 50/100

Finally, let's add the fractions:
(4 + 20 + 25 - 50)/100 = -1/100

Therefore, the simplified expression is -1/100.