Would these rims be safe?

[67DARTGTCONV]

Would it be safe to run 4 or 5 inch wide 15" rims on the street or highway.
what size of tire would also be safe?

 

[1968FormulaS340]

Yes. Just make sure you get the correct size tire for the wheel and the tires have the correct load rating.

Don't go pushing it hard in the corners.

Something like a 195-70-15 is about right for the wheel and 25.7" tall. (This would be for a 5" wheel)