How can I enable the insert rows option in my Microsoft Excel 2010?

Try this:
From your worksheet, press Alt + F11.   careful, that's ALT + F11
Next press Ctrl+G
Type in (or copy here and paste)
Application.CommandBars("Cell").Reset
Then press the Enter key.
Press Alt+Q to return to the worksheet.
Click your right mouse button on any worksheet cell.   Does your right click menu appear now?