Regarding your general performance concerns, I'll point you to here:
"Improve performance"
But, really, since you say that you're "VERY new to After Effects", I very strongly urge you to begin at the beginning and learn the basics:
http://blogs.adobe.com/toddkopriva/2010/01/getting-started-with-after-eff.h...
BTW, 5GB is a strange amount of RAM to have installed in a computer. RAM comes in sticks, and these sticks fit into slots. If you have 5GB, you have sticks of varying sizes---whereas most people get sticks all of the same size and put those into the slots. There are many reports of weird problems and poor performance with mismatched RAM sticks.
Also, 5GB isn't very much RAM for After Effects. You likely shouldn't be using Render Multiple Frames Simultaneously multiprocessing with that amount of RAM. If it's on, turn it off for now.
> It's looking like a minute and a half of video is going to be over 10gb once rendered.
For this, I'll point you to this FAQ entry:
http://forums.adobe.com/message/2989384
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Todd Kopriva, Adobe Systems Incorporated
Technical Support for professional video software
After Effects Help & Support
Premiere Pro Help & Support
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