LOL! The crème/Crimea part of the joke is just as funny in English, and it got laughs from some of my Facebook friends who don't speak Russian.
The коляска/Аляска wordplay can't be directly translated, but I thought of a similar English pun that works well enough:
After the small misunderstanding over the crème that Alina had wanted, Vova wasn't sure what to get his wife as a birthday gift. So he decided to seek the opinion of Alina's close British friend, Rosemary.
"Vat you tink Alina vants for birzday?", he said in English.
Rosemary wasn't sure: "Hmmm, maybe I'll ask her?"
Two days later, Sarah Palin became the first American woman to shoot a Russian paratrooper in her own backyard...
Let's see if I can make that work in Russian, too:
После ошибки с "кремом" и "Крымом", Вова не знает, что подарить Алине на день рождения. Итак он обратил к Розмэри, подружке-английской Алины.
"Vat you tink Alina vants for birthday?" -- говорил Путин, по-английски.
Розмери подумала и говорит: “Hmmm, I don't know — maybe I’ll ask her?”
Спустя два дня, Сара Пэйлин становится первой американкой, которая застрела русского десантника на своём двору!