I don't know French, and just need to write this amount in French:
How can this value be represented with words?
The value 129,29 € may be pronounced/written “cent vingt-neuf virgule vingt-neuf euros”, however for a money amount (especially on a check) you usually split the monetary unit (euro) from its subdivision (cent, “centime” in French) in the phrasing:
cent vingt-neuf euros et vingt-neuf centimes
(“cents” instead of “centimes” will also be completely understood/accepted.)
You can use this service on lefigaro.fr to obtain the wording of any number.