Hi Rosemary,  Evapo-Rust is the way to go!  First, go the MMD
Archives and read the several articles there.  Here's the URL link:

https://www.mmdigest.com/Archives/KWIC/E/evapo_rust.html 

Second, Evapo-Rust is a water based material.  So, if you leave
a disc in Evapo-Rust for an extended period of time, the water in
it will soak through the ink or paint on the disk and loosen the
lettering.  It doesn't "dissolve' the ink.  It comes off like
a water-slide decal, so, if you're very careful you can slide it
back in place.  A bit chancy, though.

On the other hand, anything that will protect the lettering from
the water will solve the problem of floating lettering and graphics.
Several things have been suggested, although I haven't tried any of
them.  Here are a few: petroleum jelly; lacquer; shellac; varnish;
polyurethane.

If the rust is very light, a short time in the Evapo-Rust should do
the trick.  If it's more severe, you could put the disc into the
Evapo-Rust for a couple hours.  That would clean up any light rust
around the lettering.  Then apply some protection and dunk the
disc for a longer time to remove any severe rust.  It would be
interesting to see if putting a disk in Evapo-Rust five times (for
2 hours each time with time to dry in between) would have the same
effect on the lettering as putting it in for 10 hours.

There are a few other tricks when using Evapo-Rust. If you call me
on the phone, Ill be happy to share them with you.

Regards,
Craig Smith - no snow yet in Western New York.