The red ones. There are black berries there too. This is vining up a largish shrub. I don't know the black berries.
Celastrus orbiculatus is a woody vine of the Celastraceae family. It is commonly called Oriental bittersweet. Other common names include Chinese bittersweet,Asian bittersweet,Round-leaved bittersweet, and Asiatic bittersweet. Celastrus orbiculatus was introduced into North America in 1879, and is considered to be an invasive species in eastern North America. It closely resembles the native North American species, Celastrus scandens, with which it will readily hybridize.