Metamagy and spontaneous conversion.

[InvisibleBison]

A) I'm not sure, but I'm inclined to think not. The cleric's spontaneous conversion feature doesn't say anything about metamagic, and in general in D&D you can't do something unless there's a rule that says you can.

B) You use its normal level. Applying a metamagic feat doesn't actually change the spell level, just what level of slot it has to be prepared in. The exception is Heighten Spell, which actually does change the level of a spell. A heightened searing ray prepared in a 6th level spot could be converted to mass cure moderate wounds.

[Clementx]

It functions the same way as a bard or sorcerer uses metamagic. Spontaneous Silent CLW is a 2nd lvl spell slot and takes a full round action to cast.

If you a referring to what happens when you spontaneously convert a spell slot that holds a metamagicked spell, you use whatever level the slot is.