Maybe you have a bad filter.

Will a phone work with a y-splitter at the jack the dsl modem plugs into ?
Will a phone work when the dsl modem is unplugged?

I wouldn't think one bad filter would account for no dial tone at the other jacks in the house. That being said, I am under the impression that Verizon tested your line remotely and has not actually dispatched a technician to your home.
When the line is tested remotely it measures resistance and capacitance of both wires to each other and each wire individually to ground. This data is compared to the data stored from previous tests at that service address. This test probably ran clean all the way to your NID.
Inside the NID is usually a capacitor that simulates the capacitance normally found on one phone set. If the remote test detects that capacitor at the NID then Verizon will tell you that the problem is inside your house.
I have seen a DSL synch up with only one of the two wires connected (which would give you DSL and no dial tone).
I would also suspect that disconnected wire is grounded (which would allow your phone to ring; but since the disconnected wire doesn't allow the circuit to detect the lifting of your receiver it never answers the call and the phone will continue to ring when you place it back on hook).
My suggestion is that you have someone a little more tech-savvy tackle this problem for you. You would need to find the NID because I suspect the problem to be in the NID or very close to it.