Language Issue

Well, for Barcelona I wouldn't worry, for starters Spanish is not even the local language, Catalan is, which in fact is the local language in the whole region of Catalonia (Spanish is co-official though and widely spoken by a chunk of the population) and for those knowing French is far easier to understand/read Catalan as both languages have a lot of similarities.

Nevertheless, it doesn't really matter because in Barcelona -where we have some 18-20% of residents coming from over 120 different countries- English is spoken (or mumbled at least) and is, somehow, a de-facto third language in many places (restaurant menus, the panels at the museums, etc). Same goes for websites. Don't expect to maintain many fluid conversations in English nor that everybody speaks good English, but basic communication is perfectly easy to achieve.

It doesn't hurt though, on the contrary, to learn a few basics in Catalan, you know, the hello-goodbye-thankyou sort of phrases. It's always a good sign of respect to your hosts even if just to throw into a conversation maintained in English. This way you will get even warmer attitudes when trying to communicate with us locals: http://wikitravel.org/en/Catalan_phrasebook

As per mobility (train, metro, buses), all our network here in Barcelona is majoritively based on pictorial signage, which means it doesn't matter which language you do or don't speak. See some examples: http://www.tresdisseny.com/metro-barcelona.html

you can save up to 65% on some tickets by booking as far ahead as possible (usually 60 days before but some times up to 90 days before). Times are posted in an illogical manner so one has to persevere. Renfe cot com is Spain's train system with english language option, but I suggest you read about train travel in Spain as described by seat61(dot)com. He's 'the guy' for train travel info.
Don't get Eurorail passes. all sorts of add on costs.

Tickets are cheaper to reserve a couple of months in advance and the longer the route or faster the train, the bigger the savings. You can see an overview of full-fare, 2nd-class ticket prices on Rick’s Train Travel Time & cost Map. You can also buy online on relatively short notice, since these are e-tickets.

If you are buying tickets in person in a station or at a Renfe ticket office or travel agency outside the station, then it helps to have some key details written down - destination, approximate time, class, number of passengers, and if you're looking for senior (with Tarjeta Dorada) or child discounts. In addition to Renfe, the Deutsche Bahn link at Looking Up Train Schedules and Routes Online makes it easy to find schedules when you have Wi-Fi or to print them at home (doesn't sell tickets).

I also recommend taking the Rick Steves Spanish Phrasebook to help you find, learn, or at least point to key phrases.

In 2015 my wife and I visited Spain. We were apprehensive about the language issue. We took the train from Madrid to Toledo, to Segovia, to Granada, from Granada to near Gibraltar, and back to Madrid. Every time that we needed to speak to someone with English at the train station an employee would say "I speak a little English" and it was always enough. One time when were having a trouble understanding how to use the ticket machine for the Madrid Metro a gentleman showed us how to use it without speaking a word of English. Gracias, por favor, and few phrases will take care of most of you issues. We really enjoyed Spain. The railroads are great.

Try a few smartphone apps, like Google Translate. Download the language data so you'll have it off-line.

A great resource that you can use offline (just download the language(s) you want) is Google translate app. You can type, speak, or even use the camera on the app to translate. It will even pronounce the words for you if you touch the arrow then the little speaker icon. It's a game changer in my opinion. I have no fear of fumbling for words when I know I can easily access the right words quickly. Also, for our trip to Spain coming up in Sept., I've been learning Spanish with the Duolingo and Memrise apps. Both are super easy to use, and the Memrise even offers Castillian (Spain) spanish vs Latin America spanish. But even if you don't want to do that, Google translate will be your new best friend!

I had no trouble in Spain. Learn the basic polite words - please, thanks, etc. Other than those, the most useful word I learned (thanks to a post from Brad) was aseos (toilet). Know the names of the sights you're going to in Spanish so if you need directions, the local you ask will understand where you want to go and be able to point in the right direction. It helps to know the local pronunciation . . . the last syllable is accented unless there's an accent over another one (like Córdoba), J and soft G are pronounced like the CH in the Scottish loch (or if you can't manage that, then H), in Andalucia, Z is pronounced S at the beginning, otherwise TH. Except in Barcelona, where it's all a bit different, but Enric will explain all the differences between Spain and Catalonia if you ask him.

One other tool is the book PointIt. full of photos that you, well, point at. Everything from train to pharmacy that are useful to travelers. It is slightly bigger than a cell phone and thinner than one.

Thanks for the great information! I had forgotten that I have a picture pointing booklet (not the same as mentioned here).

Debbie

Agree that you won't have any real problems. English is not as common in Spain from older folks, but most people in tourist oriented interactions you'll have will know just enough for you to get buy. And people are nice and will respond to politeness on your part. I know a little French and a little Spanish and have never had a problem even when someone didn't speak much English.