I vaccinate for everything except the botulism, but I take them for lessons and going to show. IF you horse doesn't meet other horses (meaning no trail rides in big company, no shows, no lessons in other barns) then I'd personally go for rabbies, tetanus, Eastern and western encephalomyelitis, and West Nile (although this one is pretty rare). Funny enough I just discussed it with my vet yesterday: what would be a must if no interaction with other horses. BTW, I'm not sure about Ohio but in MD you can't give rabbies yourself (the only vaccine you can't), but say in PA you can.
Edit: you can get 5-way vaccine, which also includes Rhino/Flu. That would be my pick all together.