They're pronounced the same, so you won't be able to tell the difference from how they sound--you have to go based on the the subject pronoun that comes before it. "es" is the second person singular form (you are), "est" is third person singular form (he is). So you would say "tu es" or "il est".
No, that is not true, it has the same meaning, except that the French use different words for 'eat'(after a 'you') than the one they use for it when it is after an 'I', same goes for is/are (we only use 'is' and 'are' because I is for 1 and You can be for more than 1) e.g: 'I eat cheese.', 'Je mange du fromage' and 'You eat cheese', 'Tu manges fromage'.
In many cases, see here: http://french.about.com/od/grammar/a/pronouns_stressed.htm
In the example above it's because there's more than one subject.
Except that the sentence "tu es va lion noir." doesn't make any sense, there is no particular rule to differentiate "un" from "va", since they sound really different.
There is no "v" sound, but you probably confused it with the "z" sound, which is used because of the "liaison" between "es" and "un".
If it can help you, you can try the same sentence here, to see if you can hear it better :
Not exactly. "et" has an "é" sound. "est" and "es" have an "è" sound.
Here are links with native speakers :
http://www.forvo.com/word/et/#fr (all three are correct)
http://www.forvo.com/word/est/#fr (only splouf and clador06 got it right)
http://www.forvo.com/word/es/#fr (mgersin pronounces the "s" at the end, which shouldn't be pronounced, so I recorded my own version)
These can vary from a region to another, some regions in France pronounce "et" and "est" the same way, even though originally there is a difference.
Like any new language you have to train your ear to recognize the different words and sounds. It helps to expose yourself to native French speakers. I have a native French speaking friend but when he's not available I listen to French radio (satellite) or listen to YouTube videos to enhance my listening skills otherwise it all sounds like gibberish lol
I distinctly hear a "z". Perhaps it's just that it will take some time for you to get accustomed to these new sounds. French, Spanish, Portguese, Japanese etc all have different sounds. That's why when you're listening to someone speaking English who is not a native English speaker and they pronounce words in a certain accent, it sounds weird to you. They're not familiar with these subtle differences in pronunciation in English no more than you are familiar with the subtle differences in pronunciation in other languages.
"un" or "une" can mean both the indefinite article "a/an" or the number "one".
However, in this context, we can't mean to use the number, since we ourselves decided to designate one person.
Except for some really specific context, such as talking to a person who would have the power to split himself into one or several animals for example. Then using the number could be used, if needed to specify the form the person took this time. But I don't think this situation is very likely.