The usage of is when looks fine to me. Sentences using is when are definitions of events.
When is the old english letter Æ/æ modernised to A, E and AE?
The first one is correct. The second is wrong. The reason is that you cannot use the Simple Future tense in Time Clauses, so those ones that start with when, while, before, after, by the time, as soon as, etc. In your case, the Present tense is adopted; so, the correct sentence is: The software will be installed when the computer is ready.
differences - "When X is" or "When X will be"? - English Language ...
Using "yourself" and "ourselves" in these contexts is incorrect. "Yourself," "ourselves," and "myself" are reflexive pronouns, correctly used when the subject/actor of the sentence and the object/recipient are the same person or group. "I see myself" is correct because I am doing the seeing and am seeing myself. In your latter example, the subject is the implicit "you" and the object is ...
pronouns - When is it correct to use "yourself" and "myself" (versus ...
The three auxiliaries that end in /z/ -- has, is, was -- can all be contracted to just the /z/ at the end of the subject NP. This is normal in ordinary speech, and just about obligatory for subject pronouns, so he's can mean he was, he is, or he has; the form of the verb that follows will determine which one. And, yes, when is the subject of that question, even if somebody said it can't be.
Why my downvote? Because single-word-requirest that paint themselves into a corner (e.g. it must be a single noun or a single verb) or that ask for a word which must meet an impossible condition (buying something for free) or that are too particular in the set of requirements (a word for the sense of surprise you feel when someone you don't know is knocking at the door after sunset) are ...