Will update this post and answer your questions in an hour...
Edit - Ok here we go.
- What's the difference between 3D ready and Full 3D?
3D ready are displays which had somesort of 3D capability. As you may know, there are various formats for 3D, all of which accomplish the same stereoscopic effect. There were no standards for 3D prior to 2009 and HDMI 1.4 hence various companies supported various 3D methods. All those displays were called "3D ready"
Full 3D means that the display is capable of displaying 1080p resolution for both eyes and is certified with the new HDMI 1.4 standard.
- Does a smaller screen make it worse?
For gaming, a smaller screen is fine since its more about immersion with gameplay and 3D visuals. For movies and other stuff which only require viewing, smaller screen is definetly worse. I have a 67 inch DLP Samsung which is 3D ready using checkerboard 3D method (each pixel shows different image for each eye - 720p per eye) and a 22 inch Viewsonic 120 hz monitor which is 3D ready using frame sequential method (2 frames flashing at 60 hz per eye) and I pretty much don't use the monitor anymore for 3D. There is no contest...
Note: there are no small screens which are HDMI 1.4 certified yet. 40 inch is the smallest. I will explain later...
- Are the glasses that come with the screens good?
LG ones I have not seen yet but Samsung ones are good. Sony ones, you bet. But Panasonic ones...god awful! They let too much light in as they have gaps on the side. They were made like that because of people that have glasses already and may want to wear them on top. Best Full 3D TV (panasonic plasmas) come with worst glasses, go figure. Luckily there are companies like RealD and their Xpan 103 series as well Nvidia 3D vision ( needs a PC and doesn't work with Full 3D tvs yet but will soon) which are wonderful.
Making the decision for what kind of 3D display to go for you should depend on your level of willingness to play with technology and settings.
New 3D TVs will work with the Sky 3D HD box so you can watch 3D soccer, they will work with PS3 and they will work with 3D bluray with minimal to no involment from you. However they are pricey (2000 bucks for 40 inch in USA) and glasses are pricey as are the bluray players. If you have 4000 bucks to spend and you jsut want the TV delivered and plugged in and have everything work out of the box...this is the way to go.
If you are somewhat tech savy and have the patience to work with settings and equipment and are willing to buy (or already own) a PC with a high end video card, you have a much wider choice of displays and technology you can use. Using this method you can watch Sky soccer, and you can watch 3D blurays. One thing you won't be able to do is play PS3 3D games... but you will hardly notice it after you play Metro 2033, Just Cause 2 or Battlefield BC2 in 3D on the PC.
If you are looking for something smaller (22-25 inches), the later method is the only way to go for now.