Set Up Excel 2007

Excel Options

Advanced > Editing Options
Enable AutoComplete = off

Proofing > AutoCorrect options
Correct two initial Capitals = off

Open Spreadsheets in New Window

HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\Open
rename ddexec to ddexec-old

HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\Open\command
(Default) - replace /e with "%1"
command - replace /e with "%1"

References: 

techierambles.blogspot.com/2010/03/open-excel-spreadsheets-in-new-window.html