Problem with IE 11 keeps crashing

I've been fighting with IE11 for this problem for weeks. SWMBO uses Yahoo.com for the home page in IE11. She nearly refuses to use FF and complains bitterly about our computer being "messed up". Yahoo.com works fine in FF v41. I finally got around the problem with IE11 stopping working by putting the offending website URLs in the trusted site list and dropping the security setting for the trusted sites until Yahoo would load without crashing IE11. We are at IE11 v11.0.9600.18015. I'm not sure, but I suspect MS has been altering what the various security levels and certificates do in IE lately, but I have no real proof. I'm still trying to understand how ActiveX filtering works in relation to various web sites. In addition to Yahoo.com, I had the same issue with Variety.com, except it wouldn't crash IE11, just the page would not load with no errors. Again, this site worked just fine in FF. Here's what I did to keep IE from crashing.
1. Open the tools drop down box.
2. Select Internet Options at the bottom of the box.
3. Open the Security tab.
4. Select the "Trusted Sites" icon at the top of the panel.
5. Click the "Sites" button on the right side of the panel.
6. In the "add this website to the zone", enter the Yahoo URL (https://www.yahoo.com).
7. Click the "Add" button.
8. Click the "Close" button at the bottom of the box.
9. Click the "Apply" button at the bottom of the zone box, then click the "OK" button.
10. Restart IE to make sure the change was applied.
11. If the problem persists, try reducing the security level for the zone to see if it works. I had to do this for Yahoo.