I just thought I would highlight quickly an article that caught my interest as I saw this question come up at least once in the forums the last week.
Andrew Zimmer is a developer for Avtex (I used to work there also back when they were known as Inetium). Andrew took over as their CRM developer after I left to go pursue other opportunities.
He wrote a nice article recently about how to disable all form fields on a CRM 2011 form that I think is worth a quick read, it's just a couple simple jscript snippets.
Check it out:
I hope this helps!