How to create data copies SQL Server 2005 Express ?

Question

Case 1:
Suppose there are two computers (Ser1, Ser2) and SQL Server 2005 Express is installed on each machine, the input will be stored on the machine Ser1, if the data changes on the computer Ser1 will be updated again computer Ser2, the ask my SQL Server 2005 express can update data on the computer Ser2 from Ser1 ? How the computer config ?

Case 2:
Suppose there are two computers (Ser1, Ser2) and SQL Server 2005 Express is installed on each machine, the input will be saved to Ser1 or Ser2, meaning that if the computer Ser1 busy, it will save computer Ser2 or else, and 2 machine Ser this is always synchronized data.

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