I would suggest to choose the most free flowering, vigorous and disease free rose as possible for obvious reasons. In pale, almost whitish pink category, Awakening is stunning, almost English rose-like double blooms; New Dawn and Penny Lane are famous for being a very easy to grow and free flowering, succeeding almost in any situation. Classically shaped, lovely flowers.
The above can be seen on Peter Beales Roses website, just print the name in search and voila....
From English Roses, Generous Gardener gets great reviews, don't have it (yet), but check it out on David Austin Roses website.
I love my St.Swithum and George Galway, can be seen on David Austin site as well.
For yellow climber, Graham Thomas Climbing would be a good choice.
Compassion is probably the most rewarding one, it just keeps on flowering and grows so very quickly. Check it out on Apuldram Roses website.
There are so many more but these are really sure bets in terms of being healthy, vigorous and free flowering climbers.
I would go with container grown rose, firstly, because it's a bit late in season to be planting bare root ones and secondly, the container grown ones will give you a good show within weeks.
Check out your local nurseries, they often stock more popular roses from famous growers.
Most important thing to ensure a great display is to tie them as soon as possible to get the stems into horizontal position. Basically just tie a garden twine (soft one) around the middle of the stem and GENTLY pull it down to as horizontal position as possible without breaking it. Then fasten it to the trellis. Take the next stem and bend it in opposite direction. You'll end up with a 'fan' of sorts. The reason for this is the horizontal positioning encourages lateral growth (new stems will pop up along the bent one), meaning, you'll get many more flowers!
Good luck, roses are actually very easy to grow, Water them well and read an occasional sonnet by the Master...
That which we call a rose
By any other name would smell as sweet