In general you need at least a OpenGL 2.0
I believe VBOs were introduced in OpenGL 1.5. Although my OpenGL 1.4 card supports VBOs so some cards had them early.
In my extended Version it only uses VBOs when supported elsewhere it fallsback to standars VertexArrays etc. .
You shouldn't always assume VBOs are quicker than vertex arrays. Whilst it is generally true, in my tests some cards with shared memory are faster at vertex arrays than VBOs.