Is my Hard Drive Failing?
Your drive is very happy to do a self-test; from the summary, it has done more than five of them in the past hour. And all of them have failed, early on in the test, with read errors.
Yes, this hard drive is failing. As the famous Google Labs report said (though I can't put my hand on a link to it at the moment), if smartctl says your drive is failing, it probably is (I paraphrase).
Edit: don't try to save it. Get all the data off it, and replace it.
To answer your question, a failed SMART test is a surefire indication of imminent drive failure. You should back up your data and replace the drive as soon as possible to prevent potential data loss.
@sj0h mentioned the Load Cycle Count, which is very high at 447,630. (Most modern hard drives are designed to withstand 600,000 load/unload cycles.) This is typically caused by the Advanced Power Management (APM) feature, which tries to conserve power by parking the heads (unloading them from the platters) after several seconds of idle. The heads are loaded back onto the platters when needed. On most systems, where hard drives get intermittent, on-and-off activity, this can cause lots of load/unload cycles to occur. To turn APM off, run the following command at a root prompt:
smartctl -s apm,off /dev/sda
This command will need to be run each time the system is power-cycled or put to sleep or the drive is otherwise powered off, as this setting is not retained when the drive is turned off.
In my experience, doing this will dramatically reduce the number of load/unload cycles and consequently the chances you'll experience this sort of failure again in the future. Do note, however, that doing this increases power consumption and drive temperature. If the drive constantly runs at temperatures in excess of 50 °C, the risk of premature failure is increased, so you may want to leave APM on (or turn it on if it is off) during the warmer months.
Apart from the read failures, consider also the Load Cycle Count. At nearly 500,000 this may indicate a reason for failure, or at least high load cycle wear. There is a load cycle for every minute of power up time. After you replace the drive make sure that the new drive isn't doing this as well.
Yes, you have 16 sectors unreadable, you have tried to do several tests that all have failed in roughly the same area of the drive, so, backup fast, but keep in mind that you have data already inaccessible by now lingering in the vicinity of sectors 92290592, 92290596.
You may have other problematic areas, you still don't know if those 16 sectors are consecutive or spreaded, if you want to play after backup you can do selective self-test with -t select,startlba-endlba.
Current_Pending_Sector means that the hard disk firmware has tried to read it, but cannot, it will try a few times more (whenever the OS asks for it) until failing and marking it as Offline_Uncorrectable or will substitute the damaged sector for another spare sector if the OS writes to it (thereby increasing Reallocated_Sector_Ct when doing so).