My firearms.
Real life zombies wouldn’t be magical, they’d just be normal old weak human bodies, like their host humans were before they turned. So yeah, hollowpoints or higher calibers… Will definitely do the job.
But I’d barricade my door, since it’s the only real entry point. Hunker down, stay quiet. Try to ration my food and water through the winter. Again, real zombies wouldn’t be magical… they’d die off in the first few months, particularly as we head through winter. They aren’t going to make fires, they aren’t going to put on coats, they aren’t going to avoid the elements. They’ll get hypothermia. Also, they’ll fight and eat each other constantly, for massive attrition overall. And any injuries they sustain would just let them bleed out or get severely weakened as they get infections and such.
Yeah, I’d hunker down, try to save my weapons and ammo. Let the zombies mostly all die off. If I can survive by scavving my building’s other units for food and drink, I can make it to spring and by that point it will be a massively depopulated world.
Other surviving humans are going to be a way bigger problem than zombies.