Your VAR's support team might be able to give you more in depth help, Wesam.
In the meantime, yes, all of the "updates" are full installation packages. It auto-detects whether the system you are installing it on already has Laserfiche. If it does, it upgrades. If not, it installs fresh.
After upgrading, the first time it goes to launch the repositories it will automatically update their databases in SQL.
A couple of warnings - when upgrading to 9.1, if you have been using a "Service Account" to run Laserfiche, be sure you remember its password. It will clear the password and require you to reenter it.
Also, if you are upgrading Forms, be sure to read the "List of Changes" article related to Forms 9.1 as it has some explicit instructions about backing up certain settings.
Finally, Workflows that run on a schedule (for example, once a day) need to have their schedules reset. You'll need to go to the Rule Manager on each of those Workflows and set the "start date" to something in the future, as I noticed it forgets to keep running them on schedule after the upgrade.
As you can see, it might be a good idea to enlist your VAR's assistance. Good luck!