I am using Professional, not Basic so Im only guessing they work similarly.
If TP/SP both have the same last name, it will automatically put them in the format you show above.
You can add a blank space to the end of the spouse last name then it will print
TAXPAYERFIRSTNAME LASTNAME and SPOUSEFIRSTNAME LASTNAME
In order to get them to print on separate lines, you'd need to go in and change the formatting on the client invoice/letter itself.
It will print in whatever case you have typed in the Personal Information section, if you have it typed in all caps, it will print in all caps.