Ojama King and Ojama Knight

I was wondering if anyone could tell me the rules regarding these monster effects. The effect of Ojama King reads: Select three monster zones, these zones cannot be used while this card is on the field. Ojama Knight has a similar effect. Select two monster zones on the field, they cannot be used. My question is this: can you select a monster zone occupied by a monster for this effect, and if so, what happens to the monster in the zone. Also, with Ojama Knight does this effect stop when it is destroyed, as it does not say when the effect is nullified.

http://yugioh.wikia.com/wiki/Card_Rulings:Ojama_King

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i recomend u to read up some other rulings similar to "use this, u cannot do that"

Thank you!