Text not showing up in admin is usually indicative of one of two things
1.) Language files (/Themes/default/languages) were either not overwritten with the new files (the 1.1 files won't work) or
2.) Using a language other than English (including English-utf8, for example). Most language packages aren't yet updated to work with 2.0.
You can check the above by using an FTP client to check the last modified date of the file. The upgrade does require that all Theme and Source files -- practically all files, be overwritten with 2.0 versions.
For the languages thing, you can look in your profile, if you are using user-selectable languages, otherwise, in admin > server settings > default forum language.
If you could go more into detail about what it is you need assistance doing, it'd be much appreciated. Thanks
