are there any final fantasy games for PSX which are not turn based ? where we can attack anyone randomly like in ([NDS]FF-echoes of time)?
Practically all the PSX Final Fantasy's used the turn based system, however Final Fantasy Tactics did deviate slightly with a more strategic take on the turn based style of gameplay. But no, all PSX FF's were turn based in some form or another.
Most would say Final Fantasy 7 would be the best choice, but it really depends on what you are looking for. Final Fantasy 1-4 have solid gameplay, not much to be desired with the storylines though Final Fantasy 5 has an even better gameplay element with introduction of the Job System, the story isn't half bad either though its more comical than it is serious. It's almost a parody of itself. Hopefully at least, otherwise its awful. Final Fantasy 6-7 have the most submersive stories, though I enjoyed the gameplay of 7 much more than 6. Much more flexible. Final Fantasy 8 has a retarded battle system which is time consuming and tedious. It also throws away the entire point of leveling up too considering enemies level up along with you, so there is no real reason to grind. Though the story is pretty interesting. Final fantasy 9 is just pure nostalgia, solid gameplay with a predictable but engrossing story. It all depends on what you enjoy, not a lot of them play the same. They offer different things. However if you want my opinion, I'd go for Final Fantasy 9. It's hard to hate unless you are a cynical asshole.
You could also try Brave Fencer Musashi, Vagrant Story and Threads of Fate. These three are not Final Fantasy related games but at least they're all from Square.
Actually you could speculate that Vagrant story is set in the world of Ivalice which is also home to the Tactics and FFXII world. They do share common elements.
Indeed seeing as the fictional Chronicler who is telling us of the events that occurred in Vagrant Story is the same person.... Olan/Orran/Orlan Durai.
Xenogears is a game you should take a look! One of the best PSX role-playing game you can play... Great gameplay (Vastly diferent than those on FF) Great Story, Great characters and really long!