Roll-Monroe-Co

Again, it's not clear what the problem is. If it were me, I'd take the bike completely apart. As for the rear derailleur, it would no doubt go bloop into a bucket of degreaser overnight, then come out nice and grease-free the next day and be evaluated for whether it needs an oxalic acid bath. When I was satisfied, I would oil all the pivot points and bearings inside the jockey wheels, wipe it down, and reinstall it. The Huret rear derailleur and its friend, the Atom freewheel, are not well regarded...something you understand when you start trying actually to use them while the bike is in motion. But they are original, so you might leave them there for nostalgia's sake.

PS The bearings in those pedals can also be serviced. Just carefully pry off the outer chrome cap. You'll see a lock nut and a cone nut on the outside bearings that can be removed. This will need to be retensioned when you put it all back together.

Other specialized tools you may need:

Cone wrench (a very flat wrench for dealing with the narrow flats on the "cone nuts" that form the outer part of the bearing race in a hub).

Spoke nipple wrench.

Pro-tip: When doing anything with bearings--especially opening up an old hub work over a bowl or a large fluffy cloth or something to keep them all from rolling away. Come to think of it, most of the bearings on a Conti are probably in retainers, so this may not be a big deal.