I use laptops to compose, and believe me, you don't want to use laptops for that matter. I can't even DFD properly, and all the samples are forced to be loaded into RAM, which gives me space for only a few instruments to work with. Therefore, my first buy would be a high-end computer. With 4GB of RAM, lots of harddisk space (2 harddisks), a good cooler, and a great graphics card. Of course, a professional soundcard and studio monitors are musts.
Then for software, I'd go with all the East West products(except their pianos, which is a pain in the ass when loading because of their gigantic size). Then Project SAM, Cubase 4, VSL (I want the solos), truepianos...
That's what I can think of right now.
EDITY: Next, it's time too revamp my room into a soundproof recording studio, with state of the art recording equipment, and a grand piano inside. Consequently, I will need a big cinema screen for film composing. Along with that goes a mixer, and a new keyboard.
After all that's done, it's time to hire my own orchestra, and my own brass band, and my own jazz quartet..
*dreams on*