Hmm.. small yellow that's not a miniature. That's a little tougher.
Molineux is the most attractive yellow rose I know of that grows to about
3'. Chamblee's offers this rose, along with most of the pinks and reds that
were recommended as well. Mrs. Oakley Fisher is also a nice deep yellow
that only grows to about 3', but it's blooms are single and I don't know if
that would fit your plan.

Mike