"Best" is always in the nose of the one doing the smelling, but I'll submit Marchesa Boccella (aka, Jacques Cartier), and it is easy to grow.

When I was younger, herb gardeners and others who had room for just one rose often had "Kathleen" -- a single musk. I have seen this (I think it was at Old Westbury Gardens on Long Island) growing on a pergola in autumn with pink asters beneath it, and it was just beautiful. Musk roses often have a fragrance that carries more from a distance than close up.

Here is a link that might be useful: Kathleen

I love Musk fragrance as well as Damask, both are very different scents. My 'Kathleen' rarely had as much scent as my 'Cornelia' but my 'Secret Garden Climbing Musk' was more fragrant still, as Jeri J. says of "gingerbread spices"
But if you love a rich sexy Damask scent (the type one expects from a red rose), I suggest 'Mme. Ernst Calvat' for scent as well as beauty, the fragrance is rich and seductive, the blooms are large and are a good hue of pink. We put 4 "Mme. Ernst Calvat' on tall black pillars,in a square formation, so one can stand in the middle and inhale the rich perfume. It is a short climber, just over 6 feet tall.
I've grown 'Sydonie' as well as 'Jacques Cartier' too, both also have that marvelous Damask type fragrance, but M.E.C. is a taller rosebush, which will produce more roses. Here, all of them produce 3 bloom cycles per year.

Good luck choosing what pleases you best.
Lux.

'Sharifa Asma' is very, very fragrant; and as luxrosa implies, the Hybrid Musks are wonderful, many of them with floating fragrance, many of them tending to climb, though I don't know if they get as big in your zone as they do in warmer climates. 'Felicia' has the best scent of all the HMs, a mixture of musk and old rose, and it floats, although this variety is more disease-prone than many and stays shrubby. 'Cornelia' and 'Moonlight' both waft musk scent, and 'Vanity' wafts a mild but quite perceptible sweet China fragrance.
Melissa

The White Rose of York is a big flowering shrub (wider than high) with a nice, purely sweet fragrance that gently (but noticeably) perfumes the air around it. I suspect the double version of the rose (aka the Jacobite rose) is just as nice and may bloom longer, albeit with fewer hips.

I agree with Melissa and luxrosa regarding Hybrid Musks as a great or likely best option for wafting fragrance and shrub beauty. I like 'Felicia' a would suggest 'Buff Beauty,' 'Penelopy,' and 'Lavender Lassie."

Scott

The Bourbon roses are very fragrant. I have three Mme Pierre Ogers up near my front porch, and they perfume the front yard.

Louise Odier, Mme Isaac Pereire, and Reine Victoria are also beautiful roses.

Hybrid Musks as a great or likely best option for wafting fragrance

In Graham Stuart Thomas' book on old roses he asserted that many of the rose classes dominated by Rosa multiflora heritage display that characteristic, as does R. multiflora itself.

(I have often wondered why the polyanthas are so often scentless since they also have lots of multiflora heritage, don't they?)

My favourite fragrance is Pénélope : not strong but very subtil, it remembers me the fragrance of old carnation flowers.
I also like Paul's Hymalayan Musk. In June it smells in my whole garden.

Here is a link that might be useful: A Little Bit of Paradise

I love "Jude the Obscure"...smells heavenly, grapefruity and the blooms last a long time.