Subsetting to unique values

I want to take the first row of each unique ID value from a data frame.
For instance

ddTable <-

data.frame(Id=c(1,1,2,2),name=c("Paul","Joe","Bob","Larry"))

I want a dataset that is 
Id	Name
1	Paul
2	Bob

unique(ddTable)

Will give me all 4 rows, and

unique(ddTable$Id) 

Will give me c(1,2), but not accompanied by the name column.