1a) He swims here every summer.
yes
1b) He is swimming here every summer.
never
2a) He plays tennis these days.
yes
2b) He is playing tennis these days.
yes (sounds old fashioned)
3a) I usually eat lunch at around two o'clock.
3a') I usually eat lunch at or around two (o'clock)
yes
(edit: except it's "at" or "around" or "at or around", the last being pretty wordy. "Two o'clock" is pretty wordy too, usually just 'around two.')
3b) I'm usually eating lunch at around two o'clock.
maybe in the right context, maybe not this exact phrasing. "I'm usually still eating lunch at 2, so if you could plan to come to my office closer to 3 that'd be great."
4a) Those people go to church on Sundays.
yes
4b) Those people are going to church on Sundays.
never
5a) Tom speaks English at home.
yes
5b) Tom is speaking English at home.
Weird as a standalone phrase. Maybe "Tom is speaking English at home now that his parents have enrolled in ESL courses."
6a) Tom and Jim go to school together.
yes (meaning they attend the same school, or that they commute to school the same way, or both).
6b) Tom and Jim are going to school together.
yes (meaning they are commuting to school together right now, or shortly will be; or else that they will be entering the same school).
7a) I eat bread for breakfast.
Yes, as a general habit.
7b) I'm eating bread for breakfast.
Yes, as what you're doing right this minute / will be doing shortly.
8a) I often drink coffee after lunch.
yes
8b) I'm often drinking coffee after lunch.
never
8c) I drink coffee after lunch.
yes, as a habit
8d) I'm drinking coffee after lunch.
yes, as a plan for after the lunch you're currently eating or about to eat.
9a) We read Shakespeare in this semester.
9a') We read Shakespeare this semester.
No. This reads fine as the past tense, but is wrong as the present.
9b) We're reading Shakespeare in this semester.
9b') We're reading Shakespeare in this semester.
Yes.
(edit: Oh, except as mdchachi says, 'in' doesn't belong here. I skimmed right over it on the first reading. though.)