start with dark basic pro native and then buy they addons as you have a need for them.
if you get the game studio bonanza then you will get a decent selection of these products in one hit for a cheap price.
for terrain, I choose blitz terrain because it is versatile and powerful. but for my first half year learning dark basic I got by fine using a matrix.
I like dark clouds, if you have dark clouds you dont need cloudwrite. cloudwrite makes skyboxes, dark clouds creates animated sky on the backdrop and looks very cool.(though it is system heavy.)
It really is best to wait until you actually need a plugin before buying it, if you get one by one then you can familiarize yourself with the commands. if you get them all at once then there is a mountain load of commands to learn at once.
start with native and see what you can do with it.
check out the free third party dlls. some of them are awesome.
my picks are...
sparks collision - awesome collision for game world
sparks particles - awesome particle effects
matrix1 utilities - too vast to explain in a sentence, must have plugin
2Dimagekit - extremely useful image manipulating
d3d - greatly improved 2d drawing commands
wlgfx's perlin noise plugin(great for terrains)
bbbgui - great for gui's
for modelling I like ac3d. many prefer blender. blender is free and is extremely powerful. it is the only cheap option for flexible animation. and by all accounts, once you can use it you will never look back. did i mention its free?
Sometimes I like to use words out of contents
