1) Probably no, applications will be saved, but you will need to reinstall, because some applications may work incorrectly. 2) Updates will be installed as soon as they are released automatically, there is no need to worry about it. Drivers will be updated with OS, I think, although some drivers you will need to install/reinstall manually - depends on different cases. 3) Every new version of MS OS requires more space than previous, including archives, backups etc - it will eat a lot of space, 120~150 GB of free space reserved for system needs on your HDD is must have. 4) You need to disable your AV to avoid troubles. 5) Use system restore partition (recovery function) of your PC to restore your original OS. 6) I think there will no problems with Malwarebytes on a new OS. 7) New Windows is replacing older version - you can use install DVD or recovery function of your PC to get your old Windows back. 8) Reserved update is free and will be activated automatically. 9) Let's see. Need to hope it will be better (however as always baggy and insecure).