Two of us will be renting a car after a week in La Alberca, we would like to get to Santiago de Compostela and/or Vigo and Zamora along the way.
Is this too ambitious? We will either take the train or fly back to Madrid from Santiago or Vigo. We will have only 5 days to do all this.
Any suggestions as to itinerary are welcome.

Sorry, I don't know where La Alberca is.

Last June, I flew (Air Europa) Santiago-Madrid at 07:30 the day I was scheduled to return to the U.S. from Madrid. I had plenty of time to make the connection.

I have also flown Vigo-Madrid in the past. I really like Vigo but last year I found a closer coastal resort (to Santiago: VilaGarcia de Arousa) and stayed there instead.

In Santiago, I stayed at A Nosa Casa, a Hostal on c/Entremurallas, 9. Unfortunately, the nearest Public Parking is probably the underground garage under the Plaza de Galicia (about 100m, just outside the Historical District).

According to a relative who lives in LaGuardia (Pontevedra), the toll on the toll road between Tui and Santiago is very expensive

I can't say if it is too much--I spent five days just in Zamora and didn't see half of what there was too see...

But that said, Zamora is a great town for seeing 11th and 12th century romanesque architecture There are at least two dozen churches from this era--including the byzantine influenced fish-scale domed cathedral.

Also, in the country outside of town is San Pedro de la Nave--a 7th century visigoth church with very interesting carvings of biblical scenes (as is often the case in the country, you may have to find the person who has the key to open the church. I believe her name was Concha and she lived at the end of the little "block").

In that area, we also loved Toro, which is an up and coming wine-making town with lots of bodegas and a stunning Romanesque church (La Colegiata) with a painted "portada". Next time I'm in the area, I'll probably stay in Toro instead of Zamora--I prefer staying in smaller towns.