Do not drive into Hoboken, because chances are you will not find a parking space. If you do find a spot , you need to closely observe the signs, which will state which side of the street is for residents, and which side visitors can park. In addition, there are times you cannot park because of street cleaning. It can be confusing to a first time visitor and you will end up with a ticket, or worse, booted and towed.
Hoboken is a pretty safe place. Just use common sense and you will not have any problems. The only dangerous part of town is in the western part of town and even this is only dangerous at night due to it being cleaned up a bit.