1)
What is the meaning of "Uri"?
1.
Rashi: It is praise. Be strong in your Shirah!
2.
Rashi, citing Pesachim 66b: Because she became haughty ("Ad sha'Kamti Devorah" - verse 6) Ru'ach ha'Kodesh departed from her [and she tried to get it back].
2)
Why did she say "Kum Barak u'Shave"?
1.
Malbim: He did not need to fight, only to take spoils of the enemy.