What is slowing Blender down on my computer?

So, I’m looking to buy a new computer (or possibly upgrade my current one), but I don’t know what I need to be looking for. My current problems with blender are: It crashes once in a while, sometimes it freezes for 5-30 seconds randomly, and when I try to save the project it takes a strangely long amount of time. (25-180 seconds). My spec are:

OS: Windows 10 Pro 64 bit
CPU: AMD Phenom™ 8750B Triple-Core Processor 2.40 GHz

And I have an HDD. Obviously I need more RAM, but would that fix the problems mentioned above? Do I need a better processor? SSD?

you need a new OS. win10 is a joke.

BUT, i honestly think you hdd could be failing, so BACKUP.