MCreator issue tracker has been migrated to GitHub.
Existing tickets have been migrated to GitHub. Please open new tickets on the GitHub tracker instead. If you do not have a GitHub account, all feature requests and bug reports from forums are still considered and checked by the maintainers.
1.7.9 is not the latest version. Update to 1.9.0 to get larger screen. What do you mean by unable to update?
If the DPI issue persists, check this page on how to fix window scaling: https://mcreator.net/install/windows
Make sure the computer meets the requirements too: https://mcreator.net/requirements
If this does not help, reply back in this ticket and I will assist.