Yes. Absoultey more RAM.
1GB is starving the system, and the application.
Until you can max out your RAM, some things you can do to help are:
- Lower the resolution of your comp during previews
- Disable multiprocessing
- Shorten your work area so you're previewing smaller chunks at a time
- Render a low resolution/compressed copy to disk and view it back in a media player
A Core 2 Duo is effectively 4 cores.
Each core should theoretically have 2 GB. Unless you have the 17" mbp, or one of the brand new 15" mbps, then, you can only max out to 4GB.
Yupp, definitely more RAM. Even the "normal" MacBooks now allow 4GB, and it's definitely what you will need to get decent performance out of AE. Just do the smart thing - have this done by a reseller, not Apple themselves. RAM is dirt cheap, but the fruity people have a tendency to vercharge so big Daddy Steve Jobs can make another billion...
I think on Macbooks (RIP, as this week the 13" became "Pro") the factory RAM comes soldiered in the motherboard.
So if your MacBook came with 1 GB, you can add an extra 2 GB in the other slot (check to see if it's supported, it depends on which generation is it) and go up to 3 GB total.
It's not ideal for multiprocessing on a dual core machine, but it will work.