Hi Liz,
To check the migration, focus on the things that are most important to you.
Does all the Project data, and in particular the Media, look the same?
You know what you have customised, so check those customisations look the same on both PC.
Here are some specific things to check:
File > Project Window… are the Project names and Last Updated dates the same?
File > File Statistics… are they the same?
Tools > External File Links… do they look the same without any broken links?
Tools > Fact Types… do your custom Fact Sets and any customised Standard facts look OK?
Tools > Preferences… do your customised settings look the same on each tab?
Are your lists of custom Diagrams, Reports, Queries, Plugins, etc, the same?
Create some custom Diagrams and Reports, and run some custom Queries and Plugins that you often use.
Hang on to the old PC for while until confident that everything has migrated to the new PC.