I guess the original error message meant you had a malformed C# expression in
return ((EPiServer.Personalization.SubscriptionInfo, EPiServer)...
nothing to do with the config file.
Probably you typed "," instead of "." ? (As the compiler reads this, you provide 2 types in the cast)
Revert web.config to its original version and fix the typo, that should work.
update after Greg's comment:
I didn't realize the config section you posted were part of the EPIServer configuration. You were right then to remove the assembly names.
However I guess you need to reference the EPiServer from the web app (Add Reference...). I think I noticed this in my projects too: If you checkout an ASP.Net app to a new location, you need to add all references again.