So if I understand you right, all programs crash on your PC - WED, MED and also the engine? If it's unrelated to the software I then suspect a hardware defect, like a faulty memory chip. This would also explain why the crash occurs not at once, but as soon as you load an object.

Resident software are programs that run in the background, like antivirus programs, device drivers and so on. If such a software is buggy it can also cause crashes.

Memory faults are hard to determine, but there are memory analysis programs on the internet that might help you. General advices what to do in case of PC crashes can be found on this forum under the "bugs" link.