Based on the law, my understanding is that yes, you can. The law is a bit complicated to read as it creates multiple dependencies, so we need to follow them all:
Article 6. Delay
- When an operating air carrier reasonably expects a flight to be delayed beyond its scheduled time of departure: ..
(iii) when the delay is at least five hours, the assistance specified
in Article 8(1)(a).
We have a reference to Article 8. Now let's look at 8(1)(a):
Article 8. Right to reimbursement or re-routing
- Where reference is made to this Article, passengers shall be offered the choice between:
(a) - reimbursement within seven days, by the means provided for in
Article 7(3), of the full cost of the ticket at the price at which
it was bought, for the part or parts of the journey not made, and for
the part or parts already made if the flight is no longer serving any
purpose in relation to the passenger's original travel plan, together
with, when relevant,
I highlighted the reference to Article 7, because it it important:
Article 7. Right to compensation
- Where reference is made to this Article, passengers shall receive compensation
Since the reference to article 7 is made, you shall be eligible for compensation. Note that it may be reduced by 50% if the airline offers you alternative flight subject to 7(2) - which in my experience almost never happens.
PS. Some commenters think it is greedy - but there is reason for this logic in the law. If the rules for delay were just refund of the ticket, while for the cancellation the airlines would have to pay both refund and compensation, some airlines (hello R#@$@#air) would instead of canceling your flight just announce that "your flight has been now delayed for three days" as a means to avoid paying you the compensation.