The default to pause and unpause Microsoft Flight Simulator X is the "P key". If this doesn't work you were probably changing control commands in the settings and either changed it without remembering or assigned another control to the "P key", which in turn, unassigned the pause control. To reassign the pause key go to controls in settings, double click the control you want to reassign and then press the key(s) that you want to use for that control.
There is no need to buy Microsoft Flight Simulator X: Deluxe Edition as Microsoft Flight Simulator X: Acceleration contains everything from Microsoft Flight Simulator X: Deluxe Edition and more.
Flight Simulator X is by Microsoft, the full name is Microsoft Flight Simulator X.
Microsoft Flight Simulator X: 18 Microsoft Flight Simulator X: Deluxe Edition: 22 Microsoft Flight Simulator X: Acceleration (add-on): 25 Microsoft Flight Simulator X: Gold Edition: 25
No, you cannot use the add-ons for Microsoft Flight Simulator 98 in Microsoft Flight Simulator X.
No, Microsoft Flight Simulator 2004 add-on aircraft cannot be transferred to Microsoft Flight Simulator X.
Yes, you can get a Concord for Microsoft Flight Simulator X from websites that make add-on aircraft for Microsoft Flight Simulator X.
Microsoft Flight Simulator X happened in 2006.
You can't get a car in Microsoft Flight Simulator X.
You cannot download Microsoft Flight Simulator X.
Yes and no, there are aircraft carriers in Microsoft Flight Simulator X: Acceleration (add-on) and Microsoft Flight Simulator X: Gold Edition.
Yes and no, it doesn't come with Microsoft Flight Simulator X, but you can find the add-on from Microsoft Flight Simulator X add-on websites.
No, you do not have to pay for a Microsoft Flight Simulator X account.