If the airlines refunded for every 5-minute change, Delta would be long gone, as they probably do that to at least 70% of their advance-purchase passengers.
Each airline has a time window that they determine on their own for these circumstances and publish in their Contract of Carriage; for instance, AA, Delta and UAL are currently the same at 90 minutes (but that could change at any moment, so don't rely on it.)
If it is a package flight that has changed, you would need to ask for the reroute via the vendor that sold you the package, because on a package bought from a third party the airline would not feel any obligation to check to be sure that the hotel had availability to match the changes.
(BTW, when you approach the vendor or airline, have a couple of choices of your preferred alternate flights already picked out. Most of the time if there are seats available, you will get them, and the agent will be happier with you because he or she doesn't have to waste a lot of time looking for possible alternative flights for you.)
Note that you only get one shot at a change under these circumstances; if you speak to them about it and accept the change initially, you cannot call back and ask for it later without paying a change fee. Once accepted, you are stuck with the new schedule.
(Also, note that the 4-hour thing is usually a reference to providing an airport meal voucher in the case of a delayed departure on a connecting flight.)