I'm not a fan of Ubuntu server, in part because their distribution of docker through snap can conflict with snap from the docker repo. My preference here is either Debian or Proxmox (debian + great virtualization setup). Mint is good, though I like LMDE (Debian edition) more, in part because I prefer Debian in general.
You may want to check out dockge. You do need to have docker running for it, but it's a simple setup, and it has a clean interface for docker compose. Good for getting used to it imo.
grub has no part in docker, so it's something else hanging.
What are the exact errors when you enter "docker-compose up"?