Hi Stephanie,
Great job cleaning out the basement! For cleaning when you have it emptied there is really no mad science behind it. Typically good old fashioned elbow grease is really all that is needed. I would disinfect all the surfaces if you are worried about any type of bacteria or viruses. Just make sure you get an EPA registered disinfectant and it will say that right on the bottle, or will have an EPA registration number. You can go to your local Home Depot or janitorial supply store and they will help you. For actual bugs in the basement, I would hire an exterminator to come preform an inspection and let them do what is appropriate for the bugs and any rodents. If there are rodents, don't let them use poison, have them trap them! Poison causes the rodents to die inside the walls which will smell for quite a while. The exterminators always say the poison makes them thirsty and they go outside in search of water and die out there, but that rarely happens. Animals typicall go back to their homes when they feel sick. They then become confusd and wander around aimlessly and die somewhere in the home. Plus if you have any cats or dogs and they eat a rodent that has poison in it, they are now poisoned as well. Good luck completing your basement!