I would highly recommend Cakewalk Pro Audio 9, this is a *very* powerful MIDI/Audio sequncing program which I have used for years, and I love it. The only problem is that you can only buy it on places like ebay as Cakewalk doesn't sell Pro Auio 9 any more.
I prefer Cakewalk Home Studio (version i use is 2002). Works like a charm, and it is LOADED with options and effects. A little daunting at first, but once you learn Cakewalk, everything is a breeze.