I am going in October for 10 days and wanted advice on cities and transportation. Currently we are planning on doing all travel by train, but I wanted suggestions as to whether cost and convenience would make this better by car. Also, I am 29. I am going with my wife, 30, my mother, 54, and my grandmother, 76 (but moves at least as well as my mother).
Day 1/Night 1 - Madrid/Madrid (ReinaVictoria)
Day 2/Night 2 - Madrid/Madrid
Day 3/Night 3 - Segovia/Madrid
Day 4/Night 4 - Granada (hotel undetermined)
Day 5/Night 5 - Sevilla/sevilla (Juderia)
Day 6/Night 6 - Sevilla/Sevilla
Day 7/Night 7 - Jerez/Sevilla
Day 8/Night 8 - Cordoba/Toledo (santa-isabel)
Day 9/Night 9 - Toledo/Toledo
Day 10/Nght 10 - Madrid (Carlos V)

Does this sound like too much considering the circumstances I described above? I was thinking of substituting Carmona for Granada as it would cut out a lot of travel time, and thought it might be nice to stay at the parador. I know the Alhambra must be amazing, but do you all think that it is worth the extra travel time given my short time? Anyhow, any comments on the Granada/Carmona angle or any other aspect of this itinerary is appreciated.

Yes, that is a lot to do in the time given. I've done a similar trip to all those cities but I did it in 15 days. My recommendations would be to add Avila as part of the Segovia day trip since both can be done in the same day, add a day in Madrid in which to do a day trip to Toledo, cut out one day from Sevilla, and drop Jerez altogether. Get a rental car in Sevilla to drive out to Granada and then back up to Cordoba. Do not miss Granada and the Alhambra, but in fact spend a full day there for the palace as well as the cathedral and the Royal Chapel where Queen Isabela and King Ferdinand are buried. So my recommended itinerary would be:

Day 1/Night 1 - Madrid/Madrid (Reina Victoria)
Day 2/Night 2 - Madrid/Madrid
Day 3/Night 3 - day trip to Avila-Segovia/Madrid
Day 4/Night 4 - day trip to Toldeo/Madrid
Day 5/Night 5 - early AVE to Sevilla (2hr 30min)/Sevilla (Juderia)
Day 6/Night 6 - Sevilla/Sevilla
Day 7/Night 7 - early drive out to Granada (154mi - 2hr 30min)/Granada
Day 8/Night 8 - Granada/Granada
Day 9/Night 9 - early drive out to Cordoba/ (103mi - 2hr)/Cordoba
Day 10/Night 10 - early AVE to Madrid (1hr 50min)/Madrid (Carlos V)

I suggest you combine train and car as
you are going to visit two different areas, Madrid(Toledo, Segovia, Avila),Sevilla(Cordoba,Granada)
Take a car for these three cities(Toledo,Segovia,Avila), in each one of these cities you will find good local tours or go by yourselves with a guide book.
Take a train to Cordoba and from there rent a car to go to Granada/Sevilla.
You can either drop the car in Sevilla and then take the train back to Madrid or drive back to Cordoba and take the train from there. If you drive Sevilla/ Cordoba you will pass by Carmona,it is worth a visit, or overnight stay at the Parador( recomended)
Regarding cost it is going to be cheaper to take a car for four than to pay train tickets. Except The Madrid/Cordoba trip even if it is more expensive by train is really worth it, 1 hour 40 minutes by train, 5 hours driving.
Day 1 Madrid
Day 2 Madrid
Day 3 Segovia/Avila, Night in Madrid
Day 4 Toledo,(Night in Toledo or Madrid)
Day 5 Cordoba
Day 6 Granada
Day 7 Sevilla
Day 8 Sevilla
Day 9 Sevilla (or Carmona)
Day 10 Madrid

Thanks for the help. Do you have any opinions on the bus to Granada frm Sevilla or Cordoba, rather than driving myself. Or maybe dooing the same itineray i suggested by FLYING to Granada from Madrid on the morning of Day 4 and then driving/bus to Sevilla from Granada on the morning of Day 5?

Buses from Sevilla to Granada, check in
www.continental-auto.es you have 7 times a day from 8am to 7pm 16.00€per person. The same for Granada/Sevilla
train is four times a day for 17.00€
If you want to fly from madrid to Granada there is an early morning flight www.iberia.es
rates go from 33.00€ to 169.00€ p/p
I don't know you but I never get the really cheap ones.
instead of flying I suggest to drive or take a bus from madrid to Granada.
The time you are going to spend going to the airport check in time and flight plus move into Granada is going to be similar as the drive or bus one.

This looks doable but rather rushed--particularly with your grandmother. I have some suggestions on my website that might help you--ie. a great guide in Seville (link provided). I see you do not have a hotel in Granada. I really suggest Hotel America. Go to this page on my site where I tell about it. http://www.janeandken.com/Spain2003/...stadelSol.html There is a link to it. Have you prearranged your tickets for the Alhambra? Recommend you do so. Again I have a link to that place in the Costa Del Sol section of the site. Hope all this helps. Enjoy your trip!