The shame! I can't pronounce my Polish wife's name (Ola)

Some of you might be surprised how hard it is for foreigners to get their mouths around certain vowels.

Americans i.e. the OP rarely use the "o" sound you find when saying "Ola". The example of "hot" was misleading by a previous poster as Americans pronounce that word almost sounding like "hat".

I have a Polish friend who speaks fluent English but still cannot master elongating vowels e.g Sheep sounds like ship or Two sounds like tu

They will make something between Polish Ola and Ala, and Ala is a different Polish name. Ola is a diminutive of Aleksandra, Ala of Alicja (Alice) :)

It should be just o. Clear o. Not like the name of the letter "o" in the English alphabet, where it starts to be Polish "o", but then goes to something closer to English "w", Polish "ł" or Polish "u".

You don't have to be perfect, the same as Polish people aren't perfect in English pronounciation. Think, how many Poles can correctly pronounce "th", or "a" in, for example, "man" (so that you can distinguish it from "men")? Just remember that you have to pronounce "Ola" as "Ola" (with short, clear "o"). If you pronounce it like in "coast", then if you want to spell this pronounciation in Polish, it will be something like "Oula" or "Ołla". By the way... let's get rid of "a" in "coast". You have "cost" with... something looking like exactly this kind of "o" which you need.

See: dictionary.cambridge.org/dictionary/english/cost - and play the recordings of the pronounciation. The American version is wrong (I mean, if you want to use the same vowel for Ola; in American English for coast it's correct), it goes too much towards "a", but the British version sounds - for me - perfectly OK. Even though the phonetical symbol present there looks like "a" wirtten upside down, this what I here is exaclty what is needed in your's wife name.

I believe it is pronounced OW-laa

No, just Ola.

It's pronounced almost exactly like Spanish ¡Hola!

hola.com/

Yes.
What is really important is to not pronounce it as Ula or Ala coz they are different first names and she might think he has a love affair.

English is a very poor language. It can't even differentiate between Lena and Lina. And it's Chris-tee-ahn in 99% of other languages, Chris-chun sounds terrible.

I'd only care if Central Europeans can pronouncy my kids names, don't care for stupid rosbeef Anglo-saxons.

Modern Polish has NO long vowels, so we're even!

Yep, I met an Ola in Rzeszow and thought she said Hola, but it made it easy for me to remember.

Oooola la