as a psychology teacher, I actually know some answers to things here =)
first off, everyone dreams every night. Even if you don't think you do, you do
waking up from a dream is the best way to remember it - often times that's why we remember bad dreams more than good ones
If you want to really remember a dream, write it down before you get out of bed - it will be lost by the time you go to the bathroom or shower or whatnot, then you need a trigger to bring it back - but if you write it, it sticks
ok as to the question of vividity of our dreams - 1st off there's a theory of dreaming called universal dreams, which most dreaming fits into - these are types of dreams everyone has, both good and bad - so motion for example - good motion dreams might be flying or swimming, bad might be being trapped or falling or drowning... so on and so forth
another theory sees our dreams as a way of cleaning out whats inside our minds, in this case we get a lot of randomness, so I would say yes, there is more potential for random things in our dreams because we are more stimulated now than 100 years ago
also Redz, it sounds like you're close to lucid dreaming that fun state of being aware you're dreaming...next step is to try and take control without waking up - good luck!
as for the Tylenol PM person - those drugs actually block REM (Rapid Eye Movement) sleep, which is where most of our dreams are (about 80%) so you're just increasing your NREM dreams, which are more vivid and realistic, thus more likely to be remembered, especially if something bad happens.
so I would say our dreams have more stuff in them now, b/c there is more stuff around us