I'm trying to make a lopping .gif from an animation that I made. It's 147 total frames. It's crashed about 6 times now every time I either try and Save for Web or even just save the document on my desktop so in case it crashes I can reopen PS and recover it. Making the image size smaller (original size is 1920 x 1080 with resolution 72) does not help, it still makes the *ding* error when I attempt to save. I made the image more than half of the original size and the Save for Web box actually came up that time, but when I tried clicking save it said there was an error and PS crashed without warning.
Look at the crash report for your Photoshop crashes see what they show