Will upgrade to SSD guarantee zero Application Not Responding Errors?

Solution 1:

Will upgrade to SSD guarantee zero Application Not Responding Errors?

No. While slow I/O can contribute to these errors, there are more reasons why they could appear.

Still, it's worth getting an SSD because the system will feel much, much more responsive.

That being said, 8 GB of RAM is bare minimum these days even for light Internet browsing, not to mention development and running heavy IDEs. When the RAM gets scarce the system will start moving less frequently used data to the HDD/SSD. At this point the speed of RAM doesn't matter because even fastest SSDs are orders of magnitude slower than RAM and that becomes the bottleneck.