* In English: It's pronounced eh-LAY-nee. The emphasis is on the second syllable.
* In Greek: It's pronounced eh-LEH-nee. The emphasis is on the second syllable, but the "e" sound in the second syllable is closer to the "e" in "bed" than the "e" in "lay".
If you're not sure which pronunciation is appropriate, it's always best to ask the person whose name it is.