What would have the biggest impact? SSD - Processor - GPU

Im not sure if this is the right area, and if it is not I truly apologize and request it be moved to the right area. To get to my question. I bout an Alienwere. Its by no means way out of date, but I would like to upgrade it a bit.

Specs
2.67 gigahertz Intel Core i7 920
64 kilobyte primary memory cache
256 kilobyte secondary memory cache
8192 kilobyte tertiary memory cache
64-bit ready
Multi-core (4 total)
Hyper-threaded (8 total)
NVIDIA GeForce GTS 240

I was thinking of getting a SSD for Windows seven. I then planned on upgrading to a NVIDIA GeForce GTX 560 Ti. I then started thinking maybe a new processor would give me more bang for mu buck. So in your opinion what would be the biggest upgrade. If its not one of these three please let me know.

I really appreciate any help I receive.
Travis
PS - If there is any info you could use that I missed please let me know =)

A new graphic card would increase your game play quality
A new SSD would increase overall speed on your machine
A new CPU would not do much that your old CPU did.

FPS in Games = VGA
Loading OS and Games Faster = SSD
CPU = ?@#!$#$??

I think you no need to tell us all the CPU information, Core i7 920 will do.
You might need to give more detail such as your mainboard, possible you can use some software to gather your mainboard detail (Aida64/Everest), along with amount of RAM, and of course your current PSU so guru here can give a much accurate recommendation.