the old counterstrike
 

does somebody still plays counterstrike 1.6 ?

Yep. I thought the 1.5 days were better to be honest...

I always sucked at CS. Been trying to play it since 2001 or something. Always at the bottom of leaderboard

It probably misdetects the size of memory in your PC. How much do you have? Try removing a gigabyte or two and try again; does it work then? Uhm, if I'm not mistaken, there's Counter-Strike rewritten with Half-Life 2's newer engine; it might work better on newer PC's...