Do I need to validate these train reservations?

You must validate your Eurail Pass each DAY (not trip) that you use it. Use a pen - not a pencil - and write in the current date. The conductor will check this (as you already know) and then will check your ticket.
Please check RS website here on train travel. He has excellent information on this subject.

Not in Germany. In fact, except for local transit districts (Verkehrsverbünde), there are no "little machines"; the conductor will come by and stamp your ticket or railpass and look at, and probably stamp, your reservation. In the Verkehrsverbünde, some tickets have the purchase time printed on them and are valid for only for a certain number of hours from then. Others are open tickets, valid any time, and have to be time stamped to make sure you can't use them twice. These tickets have "Hier entwerten" printed on the end that goes into the machine.

When filling in the date on a railpass, make sure you use European format (day/month/year) and European numbers ("one" looks like a droopy 7 or inverted 'V'; "seven" has a horizontal bar through it.)

Sorry, but now I'm even more confused! You say I have to have the Eurail Pass validated EVERY DAY?? Even if we don't travel?? We're only taking 6 train rides in 2 weeks. (And before anyone thinks I'm crazy to have gotten a Eurail Global Pass for 2 people for just 6 rides, I won it in a contest - it was free). My understanding is that you get the Pass validated just before the FIRST ride, then just write in the date of travel before each next trip. And, BTW, I've read all about the Pass on this site as well as books and other Eurail websites. But none of them has said whether the actual reservations had to be validated (either at a ticket window or in a machine) before getting on the train. That's my actual question.

Lee - I have no idea in which district we'll be while in Germany. Just taking the train from Frankfurt airport to Paris, then from Vienna back to Frankfurt airport. The other trips will be in France, Italy, and Austria.

Maybe I didn't make myself clear with my question. I just need to know if the actual RESERVATION SLIP needs to be punched or marked somehow by a ticket window clerk or in a machine before we board the train. If not, can we just board and show the Eurail Pass and reservation slip to the conductor without doing anything else with it.

Thanks.

Ok, maybe I can explain this more carefully.

I haven't used a railpass in Germany in over 8 years because point to point tickets, discount tickets, and Länder tickets are more efficient, but -

When I did, when I first arrived in Europe, I had to go to a ticket window and have the ticket "validated". They check my identification with my passport, and then stamped my railpass with the date to start the validity period (2 months, I think) of the railpass. It was a five day pass. On it were five boxes, one for each of the five days it could be used. Each morning, BEFORE getting on the train, I entered the date, in European format and numbers, in the next box. That "validated" the pass for that day. When the conductor came through the train, he checked that I had entered the date, and stamped my ticket, but I don't think it was necessary because, by entering the date, I had "used" that day of the pass.

I have bought tickets with reservations, but I have never bought reservations alone. However, a pure reservation is for a specific train number on a specific date, in a specific car and a specific seat. Once that train has run, if you were not in that seat, the ticket is not refundable, so it doesn't matter if it is stamped, validated, whatever. You don't have to "cancel" the reservation in one of the little machines; it is only for that train. When the conductor comes through, he might stamp the reservation, just to show he has checked it, but since it can only be used on that one train, it really doesn't matter.

Sorry I confused you by bringing up Verkehrsverbünde, but, in Germany, that is the only place where some tickets must be entwerten in the little machines.