LED T8 tube replacement
The breaker trip was the ballast dying.  It is done.  

You can replace the ballast if you like.  EBay is flush with T8 ballasts at sane cost; many are pulls from fixtures converted to direct-wire LED.  Pay very close attention to the number of wires going to each lampholder (tombstone). If each gets 2 wires, replace with preferably a rapid-start or programmed-start ballast, though an instant-start will do. If each tombstone gets only 1 wire, only an instant start ballast will wire up.   This ballast change will allow you to use the absolutely superb 90 CRI tubes now readily available (those utilitechs were junk) or will allow you to use "plug-n-play" LED tubes. 

If your ultimate plan is LED, do not use any ballast at all.   Obtain direct-wire LED "tubes" that accept power from opposite ends of the tube. This is safer and plays well with all fixtures including instant-start (LEDs with same-end power do not like 1-wire tombstones).