personal computers didn't have hard drives by default?
I do -- but the only such ones I used were in a work environment. I even had a Tektronix computer that the boss decided didn't need a hard drive so I was forever flipping floppies to compile my FORTRAN programs on it.
the operating system (DOS 3.3 and before) would not address more than 32 MB at a time?
I do -- my first computer (IBM PS/2 Model 60 - 286 without a math coprocessor) had a 40 MB hard drive and I had to partition it into 2 parts to access all of it. DOS 4.0, and DOS 4.01 quickly afterward, solved that problem.
you had to remember to "park" your hard drive before you turned it off?
That was true under DOS. The hardware eventually sort of auto-parked if not used for a bit but it was still a good idea.
computers didn't come with color display cards by default?
Even into the late '80s, monitors were monochrome (usually either amber or green) and it cost a lot extra to be able to handle color both from the monitor and the system end!
More memories?