When using a premade pie crust, what I like to do is precook the filling, first, to prevent the pie's bottom from becoming soggy.
It's because I have found that premade pie crusts take longer to cook on their bottoms, perhaps from excess sugar or moisture, or from being rolled thicker.
I like Golden Delicious apples, which are tasty and juicy, but you can also experiment with other varieties.  
PIE RECIPE HELP

You will need:
One, 9-inch premade crust, frozen; Double pan the pie crust: Place the frozen pie shell in its pan, into a Pyrex, glass pie pan. or Kelly's Perfect Food Processor Pie Dough, Single Crust
Apple Pie Filling Recipe, Step I
Crumble Topping, Step II

STEP I: MAKE THE APPLE PIE FILLING
APPLE PIE FILLING
INGREDIENTS
4 to 5 pounds Golden Delicious apples, peeled, cored, and cut into 1/2-inch wedges
2/3 cup sugar or 1/3 cup sugar or 1/3 cup dark brown sugar, packed
2 tablespoons fresh lemon juice
1/4 cup (1/2 stick) unsalted butter
3 tablespoons all-purpose flour
1/2 teaspoon ground cinnamon
1/2 teaspoon ground allspice
1/8 teaspoon ground cloves

NOTES: Here's a fast and easy way I cut my apples; I do not core them!
After peeling my apples, I cut 4 slabs of apple, staying well away from the core, and then I simply cut the 4 slabs into slices. It's a lot faster, and easier than using an apple corer.

INSTRUCTIONS
1. In a large bowl, toss the apple wedges with lemon juice.

2. Toss the apples with sugar.

3. Melt butter in an 11-inch skillet over medium heat. Add the apples.

4. Cook about 5 minutes, stirring occasionally, until the apples are barely tender. Transfer to a 7- x 11-inch pan to cool.

5. In a small bowl, combine the flour and cinnamon, allspice and cloves; sprinkle evenly over the cooked apples.
Combine gingerly with a large spoon. You do not want to break up the apple slices and turn them into applesauce.

6. Cover and refrigerate to cool.

STEP II: MAKE THE CRUMBLE TOPPING
INGREDIENTS
1 cup unbleached all-purpose flour; spoon into measuring cup and level to rim
1/2 cup sugar
1/2 cup quick-cooking oats; do not use instant
1/2 teaspoon cinnamon
1/4 teaspoon salt
1/2 cup (1 stick) unsalted butter, cold

1. Mix the flour, sugar, oats, cinnamon and salt in a medium bowl.
KELLY SAYS: A step that I like to incorporate into the recipe, is to sift the flour, sugar, cinnamon and salt together into a medium bowl, to remove lumps first.

And, then add in the oats!

2. Cut the butter into tablespoon-size pieces and toss them with the flour mixture.

3. With your fingertips, pinch the mixture together until it forms large crumbs. Set aside; refrigerate if the room is warm.

STEP III: ASSEMBLE AND BAKE THE PIE
1. Set a rack in the lower third of the oven. Place a foil-lined baking sheet on it and preheat the oven to 400 degrees F for a good 30 minutes.

2. Pour the COLD cooked apple pie filling into the frozen pie shell.

3. Sprinkle the topping evenly all over the apple pie filling.

4. Immediately place the pie on the baking sheet in the oven and reduce the heat to 375 degrees F.
If the rim of the crust begins to brown too quickly, place a piece of foil loosely.

5. Bake for 1 hour, until the fruit is bubbling. Look through the glass pie pan to see if the crust is evenly browned. When the pie is done, remove from the oven and cool on a wire cake rack until the filling solidifies more, taking about an hour or more.

Serve warm as is or with a scoop of vanilla ice cream or cool completely for longer storage.

STORAGE
Keeps for about 2 to 3 days at room temperature or refrigerate if the room is warm. Freeze the baked pie for a month or more.