1) Keep my 2.7Ghz Intel Core i7 (dual core?) and 16GB DDR3 RAM 1333Mhz
2) Improve Processor and 4GB DDR3 1333Mhz
thanks
/Edit never mind. Turns out the macbook pro has the Processor soldered to the logic board. So to change it would be to change teh entire logic board. Not really practical, and very expensive.
Okay.
So, 16GB RAM or a SSD.
Would either of those help with general running significantly?

General running being browsing, image processing (photoshop, lightroom) audio processing (Soundbooth and QuickTime / iMovie) and video rendering (QuickTime, Soundbooth and After Effects)
Thanks

Currently, to render a 15 minute video will take 30 minutes for Full HD (29.97fps) and 2x 16-bit sound channels at 44Khz sampling rate.
I would like to get that below 20 minutes if possible.