No, reservation fees are not included in your Eurail pass. Train reservations are required on most high-speed and all night trains.
No, the Eurostar high-speed train connecting London with France and Belgium isn't included in the Eurail pass. However, Eurail travelers can get a discount known as the 'Pass holder' fare.
French TGV trains and the Thalys have a limited number of seats available for Eurail pass holders. We recommend that you make reservations for the high season (May- September) as early as possible.