Internet Explorer is the "de facto" standard browser on the web (it's the most used). Outlook Express [SNIP] most used.
Got the point?
That's not a good allegory, the "goodness" of a language is measured by it's popularity and distribution, other factors are how easy it is to master, just know barely to be able to communicate, it's richness. All in all English is a very good candidate, prime factors: very spread out (especially on inet), rich both as a day to day language and is an advanced language (most recent techno-advances have names in English first), very easy to learn enough to communicate (look at all the Engrish on inet).
So until someone finds a babel-fish your best bet is English, and all the proud frenchies can got to hell :D
P.S. And Esperanto is dead for all intents and purposes since it'll never reach it's goal (being a widely used international language), some still study and speak it - so what, some still speak Kechua but it has as much future as Esperanto (maybe more).
Cheers.