It's broken, apparently some fullscreen games will crash. I could fix it myself deleting the UserSettings file in Documents/Elder Scrolls Online/liveeu/UserSettings.txt (it will be restored with Windowed Fullscreen as a default, which will not crash).
It crashed again as soon as I changed from Windowed Fullscreen to Fullscreen, so I'm 100% this is what's causing it.
If you have some confidence, you can just make sure that these two lines are in there with those values and avoid deleting your whole config file:
SET PreferExclusiveFullscreen "0"
SET FULLSCREEN_v5 "1"
It is a known issue in this version of Windows:
http://www.winbeta.org/news/known-issues-windows-10-redstone-insider-preview-build-11102
Some PC games will crash switching from windowed mode to full screen, upon game resolution change, or upon launch due to a bug in Windows graphics stack. We have observed this with The Witcher 3, Fallout 4, Tomb Raider, Assassin’s Creed, and Metal Gear Solid V but it may occur with other titles as well.
Do not panic, it's not your fault and it has an easy fix

Note: American users will see live instead of liveeu
Note2: This should only affect those who are on the Insider Preview program... for now. Everyone else is safe.
My Windows Build Version, in case anyone needs the full thing:
Edited by Ruben on January 24, 2016 5:57PM DK Stamina DPS
DK Magicka DPS
DK Tank
Templar Healer
Sorcerer Stamina DPS
Nightblade Magicka DPS
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