Well, if you are going with 'wall to wall' carpeting and you still have the possibility of flooding, I (personally) would use carpet squares. They are typically 18" square and have a rubber backing. No need to glue them down (in most instances) as the rubber backing holds them in place fairly well. Nice part is you can install these yourself. All you need is a heavy pair of shears or a heavy duty paper cutter (like you use in an office) to cut and trim your squares around the perimeter of your room.
With the squares, if you ever flood again they come up fairly easy so you can take them outside to dry and also suck up the water on the floor. On occasion I flood too. Me, I use area rugs on my basement (concrete) floor so its easy to roll them up and get them out of the way for clean up. It is a pain but I now have everything up off the floor so it doesn't get soaked when it happens. My amps are on 2" thick maple butcher blocks, stands and speakers all have spikes. Heck, I've even got my power cords and interconnects elevated.
You might think about installing a water sensor too. Mine is tied into my homes alarm system. Last time I flooded Brinks woke me up in the middle of the night with a phone call to let me know water was coming in. It saved me hours and hours of extra cleanup. You should be able to do a stand alone model with a transformer, the sensor and an audible alarm. There are several home automation sites that will have all the parts you need.
Good luck!