>>1170412In the current continuity (current for me is when I stopped reading - so like whenever death metal or whatever came out), Superman has like a shit ton of origins that "all sorta happened", so you don't need to start at a specific point, but it is good to read some recent / critical ones.
As for batman, the origin that I remember (and I think is and has been his origin since the 80's), is Year One , which is a great starting point , since it's relatively short and distils batman to his foundations. You've already read that so you basically know his origins (without the retcons from Scott Snyder's Zero year).
Apart from that, you can't read every story about most DC characters without knowing a metric shit tonne of continuity bull shit and information. The reason being that every 5-10 years since the 80's, DC has what's called a 'Crisis', which is basically an event within the DC universe that has ramifications for every character and gives DC editorial a chance to reset the universe to start on a new page and to bring in new readers such as yourself who want to jump on without reading all the way back to 1940.
Crisis's are sometimes nice, but most times infuriating.
Anyways,
Superman - Secret Origins, For the man who has everything, For all Seasons, All Star Superman
Batman - Long Halloween (imo, the sequel to year One), Batman Ego, Scott Snyders new 52 run (maybe), DKR (obviously)
Others - DC: New Frontier, Crisis on Infinite earths --> Infinite Crisis, Justice League International, Wonder Woman dead earth (cause it's pretty awesome), Maybe the Omnibus's for the Characters you like.
If you want to download comics online for free, download a comic reader onto your pc through the Microsoft store and go to
getcomics.info and download the ones you want.
ALSO, the way I got into comics was through a YouTube channel called ComicPop, from a show called 'Back issues'. check that out to get some sort of idea into the bullshit that is DC Comics.