I don't know of a neighborhood for you, but I did want to add that I'm not sure if you'll find what you're looking for near Dublin (where you work). Most of the places people have been suggesting are on the east side, and Dublin is on the northwest side.
I guess Northland is on the north side, so it'd probably be closer to Dublin than Reynoldburg, Canal Winchester, etc BUT the Northland has it's share of crime, for sure. Maybe not as much as the Linden area, but I don't know, I wouldn't call Northland a very safe area. Northland is not as safe as Reynoldsburg or Canal Winchester.
At the Ohio Dept of Education's website, it says that 3.3 percent of Dublin Schools children are black, 3.4 are hispanic, 14 percent are Asian, and 75 percent are white. So that probably wouldn't meet what you're looking for. Although I live in Dublin and it's really a very nice place to live. Wright Elementary in Dublin is 14 percent black, 30 percent asian, hispanic, and multiracial, and 55 percent white. It has the highest percentage of black students.
Reynoldsburg schools are 31 percent black, 56 percent white, the rest multiracial, asian, hispanic. Slate Ridge Elementary in Reynoldsburg is 35% black, 45% white, 13% multiracial, and 5% hispanic. It also looks like it might be a new school, which would be nice. Slate Ridge had the most black children, with French Run next.
Westerville Schools has 20 percent black, 70 percent white, 10 percent hispanic and asian. BUT, there are areas in Westerville that have more black children - but probably not predominantly black. And Westerville would be closer to Dublin. Right now I don't have time to look up the percentages in Westerville, but here is the website you can go to:
Default County Report Card Home Page
You choose Westerville from the drop down menu, and it will give you a list of all the Westerville schools. To find out the percentage of black students at each school, go to each school's "Building Report" section and choose 2007-2008. A "report card" will open up for that school. Scroll down until you see "Your School's Students" and you will see the percentage break down.
So if I were you I'd find the school that has the percentage of black children you are most comfortable with, and then look in that school's neighborhood.
To be honest, I don't think you'll find an area that is 60 - 80% black that is not inner city, which you said you didn't want. In my opinion, if safety is your biggest concern, with higher percentage of blacks your second highest concern, Reynoldburg schools would be best, but Reynoldsburg is far away from Dublin.
Westerville Schools would probably be second best in terms of percentage of black children, but better than Reyndoldsburg in terms of safety, and it would be closer to Dublin.
That's my 2 cents! Good luck!
Linda