htkaki, Probally it is not what you think. Staying in tokyo, you must know that sometime strange sound coming from wall or surrounding. It is small quake or temperature changing. Most of the building in japan are not brick and cement. Just wood, steel and partition.
I stay in tokyo for 2 month and encounter the same thing. Next day only know it is a small quake. But still not convince me. You know why. Cause infront cross a small road where I stay is a cemetary. Freak me out. hehehe...

stay in kuta. that's where the nightlife is. legian isn't much farther away but kuta's more happening

if you've got budget, mercure or hardrock. else, one of those local 3star hotels along the kuta beach road will do just fine (if you're not paris hilton)