Until the software is loaded in to the RAM it is your Hard drive that is the bottleneck.
So using SSD you will gain some speed, but make sure you keep 20% free space on the disk.
Once the software is in your RAM it is the combination of the processor (CPU) and the RAM, assuming you have sufficient RAM so not to have to share it with SSD.
After that it is the software it self that slows things down by bad design, bad drivers, or needing lots of other cross functional activity (other programs) to operate.
You can find the details of shut down and start up in your Console
var/log/system.log