IPS or VA display?

For video and image editing, you want to stick with IPS or its equivalents. IPS is trademarked by LG. PLS is Samsung's version. AHVA is AUO's version. All three do pretty much the same thing, but in slightly different ways so as not to stomp on each others' patents. I suppose OLED is becoming an option now and is the de facto best choice, but is still horribly expensive.

VA actually has better blacks (IPS and its variants tend to suffer from backlight bleed and bleed at off-angles), but its color reproduction is not as good.

And yes, you will notice the pixels on a 24" 1080p screen if you look carefully enough (it's obvious even to my middle-aged eyes). On a 27" the pixels will be blindingly obvious, so I do not recommend 27" 1080p monitors. Do note however that this is partially dependent on how close you sit to the screen. If getting a 23" instead of 27" means you'll sit closer to the monitor, the pixels may still be obvious.

Both LED and LCD monitors use LCD panels. The only difference is that LCD monitors used CCFL (cold cathode fluorescent lamps) for their backlight. LED monitors use LEDs for their backlight.

The CCFL backlights had slightly better color reproduction, but their output brightness and color changed with age, forcing you to recalibrate your screen every month or so for accurate color work. They also would burn out after about 5 years of use. They were only rated for about 20,000-40,000 hours (that's 2.3-4.6 years of constantly being on). LEDs are typically rated 50,000-100,000 hours.

The fluorescent technology meant there needed to be a capacitor inside which helped step up the lithium battery's 3.7V output into the thousand or so Volts needed to light the fluorescent tube. If you attempted to repair your screen within a few seconds or minutes of turning it off, this capacitor could still be holding a substantial charge. if you touched it, you could give yourself quite a shock. I've heard of people shocking themselves this way (a friend of mine actually did it with an old CRT, and the bastard tried to trick me into doing it too). Theoretically the shock could cause your heart to stop beating and kill you, but I've never heard of that actually happening.

Eliminating that capacitor, lower cost, and smaller packaging means nearly everything uses LED backlights nowadays.

The LEDs aren't as good at color reproduction because the cheapest way to make white light is to use a blue LED with yellow phosphors. The yellow phosphor produces enough red and green for an RGB monitor to function, but let's just say the red and green aren't "pure" (because I don't want to get into a long discussion about the eye's color receptors and color reproduction). Consequently, cheaper LED panels (often used in laptops and other devices like baby monitors) cannot reproduce the full sRGB color space which is the current standard for HDTVs and the web. However, nearly all external monitors are built better and can hit 100% sRGB.

Unfortunately, sRGB is not a very big color gamut (it was designed with early LCD displays in mind). Looking towards the future, if this video and image editing becomes serious or a profession, you will probably want a display which covers the AdobeRGB color space (it's roughly the same as the NTSC color space used in the old CRT days). These are typically made using separate red, green, and blue LEDs. Unfortunately, they're very pricey so probably aren't a good choice for someone just dabbling in graphics and video. But it's something to keep in mind for the future. OLED displays can actually exceed AdobeRGB, so I'm hoping the future is filled with OLED monitors.