I started chrono crosss and got part way some years back but never played trigger so I restarted it and hadn't played since. I have several games I hadn't opened yet just because I wanted to gather my collection. It took me 4yrs buy all the PS version of Final fantasy and I hadn't even opened some. I big on playing things in order. It just I jump from so many games I never finish hence the problem.
Well, Chrono Trigger came out before Cross so I would play that first.
And when you say you haven't opened some of these PS1 games, do you mean they are still in their original wrapper? If so, you should be extremely careful about what you open. I wouldn't even open the FF games, I would just get a used copy or since you already own a legal copy, just download them online if you have a modded PS1 or PS2. Sealed PS1 RPGs can be worth a lot of money.