I would start with Reason
Reason is capable of sooo many things. I will work on a Reason preview trak for you showing you some of the things you can get out of it. Unlike a hardware synth/sampler, you'll find things 10 months down the road that you never knew was possible.
Have you downloaded the demo yet?
A exellent resource is
www.reasonstation.net
The people are kinda techno snobbish, and you wont see allot of Hip Hop threads, but trust me- they exist.
The routing possibilities in Reason is exellent, plus is will teach you basic studio setup, midi relationship, synth programming and a track building. Allot of engineers use it. I found a site showing Nothing studios (NIN) and they were all huddled around a laptop with Reason and in the bakground you can see all of their hardware.. haha.
Anyway- download some of the tracks from Reason Station and listen closely to the sounds.
I will post some more stuff ASAP about it, but I would suggest picking it up before buying a hardware synth. It's a great source for sounds, and works brilliant with any samplists hardware.
Reason 2.5 should be out soon...