Re-entering the US on a valid H1 visa. A few questions

Hello,

My wife and I are citizens of India and have valid H1 visas. We are looking at international travel to Spain in December. I had the following questions about reentry

1. My wife's H1 stamp expires in June 2018. She has an approved extension thru 2020, but with a different company since she changed jobs after she got the stamp.

2. My H1 stamp expired in 2017. I have a fresh I797 approval up to 2020 but will also change jobs soon - new H1, I797 and all that.

We both have (or in my case, will have) approved I-797s.

1. Which of us needs a fresh stamp prior to re-entry?

2. Can we/either of us get stamps at an American embassy in Spain even though we're from India? Like I said, both of us already have H1 visas and stamps so it's not a change of status.