Elements 11 shouldn't be slow Re, especially not with Windows 8.
What editing are you doing when you see the 'edit in progress' message?
It is only a 32bit application (as is PaintshopPro), which means that 4mb ram is all it can access, so even though my PC has 16mb installed, Elements is running the same memory as you have installed. (Photoplus can access all of this as it is a 64bit application). My copy of Elements 11 loads in less than 15 seconds, artistic effects take couple of seconds to load but execute almost instantly after pressing 'OK'. I do have decent graphics card with 2gb ram on board, but I wonder if your performance has not been optimised.
Go to >edit>preferences>performance: make sure that the available ram is as close to possible to the maximum recommended in the 'ideal range' box, that'll be around 2gb, and that the scratch disk in the dialogue box below is a fast local drive.
If it still slow after that I'm not sure there is too much more you can do.