Autoruns shows you all the pieces of software that get loaded and run when Windows starts. The descriptions of each item can be rather cryptic. Use Google to get more meaningful information about any particular one.
The entries you unchecked, because they reference files that couldn't be found when Windows starts up, will not have any effect on your system because the files aren't getting loaded. Deleting the entries will save a tiny amount of space in your registry, but that about all.
Most people use Autoruns to determine if there is unwanted software running on their system. It takes a while to learn how to be able to recognize "normal" Windows modules from other ones. Your system has a lot of extra stuff running on it which suggests it was a pre-built system that the supplier loaded up with it's own software. This is not necessarily bad as long as you find that software useful or helpful.
Unchecking an item causes Windows to not load it at startup. The software itself is still there; Windows just won't load it. Deleting an entry from Autoruns also stops the item from being loaded, but does not delete it. Unchecking is a safe way to determine if the item is needed or not; if you uncheck something and reboot and then find you do need the item you can simply re-check it and then reboot to get it back.