VBA Code For Opening / Importing?

I have a workbook with a button that will run a macro to open files and import sheets based on if the user checked the box. Everything works perfectly EXCEPT for the importing of the sheets from newly opened workbook.

Here is what I want the code to do:

1. if the box is checked then open the file
2. Copy (import) the first sheet in the newly opened workbook and put it before the 1st sheet.
3. Close the workbook that the sheet was copied from and do not save changes
4. active the workbook that has the newly imported sheet.

And here is what i have thus far:

Code:
Sub OpenFiles()
Dim Folderpath As String
Dim cell As Range
Dim r, LRow As Single
Dim Dbook As Workbook
Set Dbook = ActiveWorkbook

[code]....

After stepping through it, the problem is here:

Code:
Workbooks.Open Filename:=Folderpath & Range("B" & r).Value
Source = Range("B" & r)
Sheets(1).Copy Before:=Workbooks("CompletionWorksheet.xlsm").Sheets(1)
'How the hell do I close this ^ workbook
ActiveWorkbook.Close savechanges:=False 'This closes the workbook where the sheet was copied to
Windows("CompletionWorksheet.xlsm").Activate

Not sure what to do.