The package came with the first 3 Tropicos. Should I play Tropico 1 then 2 then 3? or is there no real point in playing the old ones? Usually if there is some sort of story/campaign I like to play in order, but just installed the 1st one and there doesn't seem to be any, just scenarios.
Nope, there's no real reason to play them in any particular order. Tropico 3 is more or less a remake of Tropico 1, albeit with some different scenarios. Tropico 2 has a completely different focus, (Pirates!) so it doesn't matter when you play it.
There's really no plot or story or anything in particular that can be spoiled by playing them out of order. Tropico 3's really the most modern of the bunch, so I'd suggest just sticking with that and ignoring the other two, unless you're interested in them for historical reasons.
I'd almost say it's like playing one of the earlier SimCity or Civilization games when you have the latest one available - they're a bit different, (Tropico 2 especially...) but by and large they're just iterations of the same formula.