grammar - The correct usage of ～と決める, ～に決める, and ～を決める

Browsing the example of 決める, I found at least there are 3 patterns as follows:

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  行くと決めた。I decided to go.

  
  
  


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  行くまいと決めた。I decided not to go.

  
  


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  車を買うことに決めた。I decided to buy a car.

  
  


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  会議の日を決めた。I decided the meeting date.

  
  

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  Are my conclusions below correct?

  
  
  
  
  • ～に決める can only follow こと.
  
  
  • ～と決める can only follow verb in dictionary form.
  
  
  • ～を決める can follow any noun.
  
  
  
  
  


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  Which is the correct interpretation of「私たちは、会議の日を三月四日に決めた。」?

  
  
  
  
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    We decided the meeting date to be March 4.

    
    
  
  
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    We decided the meeting date in March 4. (But when the meeting date is unspecified)