You'll use certain shipping services more than others. And if you reach a point where you realize that some services are never used, it's best to just remove them as an available option. If you don't anticipate using a certain service, you can head to your Carriers & Fulfillment settings and remove it as an option when shipping.
Head to your Account Settings (the wrench icon in the upper right).
Next, select Shipping and then Carriers & Fulfillment from the sidebar on the left.
On the page that appears, click on the services area for the carrier account you want to adjust.
On the popup that appears, simply deselect the Shipping Services you want to hide.
These can be re-added any time by returning here and selecting them again. Click Update once you're done!