Is English more widely spoken in Brittany than elsewhere in France

Sorry, English is not more widely spoken in Brittany than elsewhere in France. The "Gallic connection" is a Celtic connection. You will notice celtic placenames (with French spelling) which sound like placenames in Cornwall and Wales. For example starting with "L" or "Tre", or "afon" (= river).
The Breton language (Which I don't think is used much) is similar to Welsh.

Don't be fearfull of being in a country where thay don't speak your language. Buy a phrase book for the basics, and just relax and have fun. If you print out this phrasebook it should be enough to survive.

Uh, no.

Then there was that time a French dude conquered England, but the language didn't stick then either.

However, what you may have heard (bear in mind that a Welsh fellow told me this and those suckers have been known to fib) is that Breton and Welsh, being both Celtic, are fairly understandable in either direction.

Edit: Breton is indeed coming back but certainly not to the extent of Welsh.

Your friends are "fearful"... er .. good luck enjoying that holiday.

To be blunt since you are renting a house.. likely staying out of a tourist center.. less people will speak English then more.. as opposed to staying in a hotel in the middle of a very touristy area in a bigger city (ie Paris)..
Most tourists don't speak French you know.. so tell friends do relax.. learn to say hello, please and thank you.. and have a sense of humor. Smiles and pantomime go a long way.

If they are truly "fearful" then you may have more issues then the language. Some folks are simply not good with change or differences.. different food, different customs, different ways of doing things.. to some people things that are different are bad or inferior. Hope your friends are not like that, it will make it hard on you . Good luck.

I traveled solo in Brittany last summer. I speak no French, anyone to whom I spoke can confirm this. Well, I rehearsed a few questions, tried my best, but was totally unprepared for the tsunami of syllables that came as a response. Pantomime and gesture saved the day.

I think you should consider how much of a holiday it will be if you and your family have to be the caretakers for the other family. I have traveled with another person recently and will not do that again in the same way. I have also traveled with two friends every summer for 10-14 days, and it works out great. You have to know your own and your companions' expectations. Saying they are "fearful" seems to be a red flag for some posters - it would be for me, too.

I would have thought that Brittany would contain departments where English is spoken even less than in other some other areas of France. It is very rural.

On the other hand, as you are fairly happy with communicating with local residents, I would think that you could put them at ease. They will be with you and your confidence will work wonders. If you know them well I am sure that that will help.

If you take them to tourist areas like the Normandy beaches, Rouen, Mont St Michel, Giverny, etc., they will get plenty of English.

Are they worriers in general, or is there anything else worrying them?

You have 11 months to go on a French class with them, or practice with them on a DVD, online, or CD.

Other than the scads of Brits with holiday homes in Brittany, French seems to be the lingua franca.
@ Ed, I think something from that French dude (a 3rd generation Viking) must have stuck, otherwise we'd be speaking Anglo Saxon. But then maybe we could speak intelligibly with the residents of Ost Friesland.

Not to overgeneralize - but here goes...we've spent quite a bit of time in rural areas of France, including Brittany, and have found that older people in these areas rarely speak any English. It will be more likely that younger people do but it's often not at a conversational level that makes communication easy. That said, we have found that in the rural areas there is much more patience for those of us who are not well-versed in French - people are generally lovely and will take the time to work out what it is you want whether it be directions or something from a restaurant menu.
If you are in a non-touristy area you will be a novelty! We are also home exchangers and had a fantastic exchange in a rural community in southern France for 5 weeks...our cute little-old neighbor lady would wave to us from her balcony every morning, shout some happy sounding thing to us in French, we would shout a happy thing back in English, and be on our way with both of us smiling and waving the whole way! The housekeeper would come over and didn't speak a lick of English - pantomime and my high school French came in handy but it was quite interesting trying to discuss when she was going to come next! Don't be intimidated by not speaking French - part of the fun is going to the grocery store and figuring out how to buy and pay for things, getting coffee at a cafe, etc...if you get into the right mindset before you go, knowing that it is an adventure and not something to be fearful of, and knowing that most people are good-natured and kind, you'll have a great time!

Hi, Kerry

This family that you are inviting have they ever travelled out of the States? What's the personality type? Easy going, able to roll with the punches when things don't go as expected, willing to try new foods and experiences? Or are they the type that wants things to be similar to what they get at home?

Does the two family have similar habits: early risers or not, like to eat meals at regular times or skip meals, like to do similar activities, etc.
We made the mistake of inviting neophyte travelers on a cruise, even though they were friends of many years. The husband was such an uptight guy that he was even fearful of not being able to find the huge cruise ship. We like to get up early and exercise. Wife wanted to sleep in late until 11:00. We're not big drinkers, they were. It was the worse ever trip. And this was easy traveling, an Alaska cruise. No problem with the language and everything was taken care of.
So, I would heed the previous posters' caution of traveling with this family. Seriously, think it over. Why do you need to invite them?