in corporate environments registy access is often disabled as the registry gives a user significant control over their PC and is a security risk.
The registry contains a whole butt load of stuff, from MRUs to settings & associations etc.
Some programs still use .ini files and windows includes some for backward compatability reasons.
Edit: I think the point you're missing is that the registry contains pretty much all the settings (including security) for windows as well as some for applications.
Intel core I7 920
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Samsung SM2443BW 24"