Nope, Dumbledore is nothing compared to Gandalf. For one Gandalf is a Maia, and others have elaborated on this, but this automatically puts him at another level than Dumbledore who is, though a wizard, still just an old man. Gandalf however is not really an old man but is in actuality a being more glorious than even elves. His true name is Olorin and his exceeding wisdom is without parallel.
Same concept for character; Gandalf is only grumpy all the time because of the hundreds upon hundreds of years that he has had to bear the burdens of: his mortal body/rainment, the various races of middle-earth and all their troubles, the ever looming threat of Sauron (a Maia far more powerful than him), the quest of the ring, and having to do all of this mostly by himself. I mean, of the five Istari that were sent to help guide Middle-Earth two completely abandoned it, another was no help at all and was mostly a fool, and one totally isolated himself and then allied with the very enemy they were supposed to be fighting!
Gandalf's been through a lot, and he wouldn't take any of that from Dumbledore, he'd be all like "Fly you fool! Before I knock you off your broomstick."
I do like Dumbledore on his own merits though.