Are you looking to do this live or just prepping the pieces for later play? Ableton Live gets very good reviews, and a Lite version can sometimes be found bundled with other software/equipment. Check for a trial as well. Fruity Loops has a strong following too, and had free versions in the past. Maybe a trial as well.
I use Sony's Acid, and there are several related versions including an Acid DJ, but I don't know much about these other versions. Acid is not optimized as much for live work.
All of these can get down to some pretty complex levels, if you want to. Those are the main ones that I am familiar with.
I'd suggest looking for trials or demos and seeing if the UIs seem easy to work with and comfortable for you.