TV tomfoolery part 1 - cracked LCD TV screen

At the school where I work, we have two 42" LG 42LC51 LCD TV's in the atrium area. One TV has an Asus Eeebox hooked up to it, and a USB mouse so the students can navigate the school timetable (and therefore have no excuse for not being in class).  The other TV also has an Asus Eeebox hooked up to it, which from time to time shows videos for various school events, or slideshows of students' artwork etc.

One day back in November we turned on the second TV and discovered it had a cracked screen, rendering the TV basically useless. We have security cameras, but their placement is so far from the TV as to also be of little help in finding the culprit. That and the fact that the TV hadn't been used at that point for 2 weeks meant that reviewing the recordings from the security cameras has not a task that anyone has really wanted to undertake wholeheartedly, and the culprit remains at large. We suspect that some over-enthusiastic football playing with a plastic bottle is the likely cause of damage, and bearing in mind our security camera's very low frame rate, you can barely see a fast moving object at all.

The TV itself is at least 5 years old, and replacing the screen was looking like it would be as expensive as buying a new TV.  So it was time to seek out a new TV.

Requirements:

1. Full HD
2. At least 2 HDMI
3. USB
4. Not SMART TV - read my other blog post
5. Must be possible to disable the buttons on the TV
6. Known brand
7. Good price

Since not many manufacturers have any feature for locking the TV's buttons, I finally opted for another pair of LG TVs, this time 42LN5400 with a price tag under 400eur.