File-saving related crash (PSD to PDF)I'vehadNow,NotiOtherthan

Question

Please feel free to rant about the other one hundred previous posts about this problem, if there are any; I certainly did not have time to look through every page of discussions just yet and typing in the searchbox did not give results.
Since every problem here seems to be slightly different and I am not a part of the annoyed Snow Leopard-users mob, I humbly but DESPERATELY ask for help on my own.
I have recently switched from Photoshop CS3 to CS4 because of a simple reason — I thought it would fix this problem somehow.
When it was time for me to save my first, extremely large file (a poster), A3-sized, with approximately 14 layers, I was told by my company to save in .pdf. Now, every single time I tried the app crashed. And surprise, surprise – nothing changed when I flattened the image, saved in .png and then tried .pdf.
Nothing changed either as I tried the same in Photoshop CS4.
I'm running a white MacBook, with OSX 10.5.7.
My processor goes up to 2.2 GHz, with Intel Core2 Duo
And I have 4 GB RAM. 
This is so far the only problem I've ever had with Photoshop, but at this point such problems are very unwanted since it interrupts my work.

Answer 1

There are a handful things you can do to resolve this:
Save as JPG. Open Acrobat Professional, File > Create > PDF from file. See if this works best for you
In your image size option within PS, the last option - Resample Image - Change to Bicubic Auto
Include a screenshot of your PDF print setting in the 'Save Adobe PDF' dialog box that pops up when you try to save your file as PDF. Look under 'Compression' options in the left side for Downsampling. Check if the value of Downsampling is less than your PS file resolution. If it is, adjust accordingly. Refer screenshot below
Try changing Compression from JPEG to 'None'. Yes, filesize will dramatically increase. But doesn't hurt to try it out to see if your image quality is as per your desire
Trust this helps.