(Tom wouldn't actually know any of these songs because for him it would be 1942 and these songs wouldn't exist yet- and they are Muggle songs so he probably wouldn't ​know they existed but I'll try. This is also to answer DanMyBebe678 's question.)

"What would be your theme"

Well to answer your question, Sarah, I don't really know. I have, however, been told often by a small brunette that both "Demons" by "Imagine Dragons", (whatever in Merlin's name that is. Why would you need to "imagine" dragons when they actually exist?) and "Emperor's New Clothes" by "Pan!c at the Disco". I don't see the point in searching for theme songs when you could be searching for information on horcruxes instead.