I was facing the same problems so I installed an ad blocker. I know NB needs the money but they should make smarter ad choices. If they are so desperate for money that they have to add such shitty, intrusive ads, then just add an ad placeholder right below the forum menu (User CP, New Posts, Private Messages, etc). Yeah, the forum will lose its appeal but sacrifices must be made if you want to continue bringing in the money.
If you're on iPhone/iPad you should get a content blocker such as
You must be registered for see links
,
You must be registered for see links
, or
You must be registered for see links
.
If you're on Android then find your own method.
For PC users just search for AdBlock for Chrome or AdBlock Plus for FireFox.