• añjasā — easily
  From √añj (to anoint, smooth). Done smoothly. Gauḍīyas note that yajña done with the right yajamāna feels like nothing — the ease is itself the testimony that Bhagavān was at the receiving end.
• manaḥ-ratha — of his desires (literally, mind-chariot)
  manas (mind) + ratha (chariot). The chariot of the wishing-mind. Gauḍīyas note the imagery: desire treated as a vehicle that carries one across an ocean — once the destination is reached, the chariot is parked.
• spṛśan — touching
  Present participle of √spṛś. Vasudeva touches Nanda's hand (kare spṛśan) before speaking. Gauḍīyas note that the Bhāgavatam often signals the gravity of a coming speech by recording a touch — a hand on the arm, dust from feet — before the words begin.
• uttīrya — having crossed over
  Gerund of ud + √tṝ. To cross up and over. The same root as tīrtha. Gauḍīyas note the structural pun — yajña has been Vasudeva's tīrtha, and he has crossed.

• What ambition of mine, if completed, would actually leave me satisfied — or restless for the next?
• Where do I assume more ambition is the cure when satisfaction is the answer?

Vasudeva has crossed the ocean of his manas-ratha — the wish-chariot of his desires — and the crossing is described as 'easily' (añjasā). Yajña, when actually executed, is not heavy. He takes Nanda's hand: the gesture of a man finished with his own business and ready to attend to the friend whose company outweighs it.