yes, you can always say to the A-kasse, that you don't want to receive unemployment benefits ("dagpenge") for a given period. You must inform your A-kasse about holiday at latest 2 weeks before going on holiday. I am not sure if you need to unregister as unemployed at the Jobcenter, but try to ask them.
After your holiday you will go back and continue in the dagpenge-system from where you left. This means that you will have up to three years (from graduation) to use your 2 years (3.848 hours) with dagpenge.
Anders Weber, www.a-kasser.dk