Regular Expressions Issue

I'm not sure if this is the correct forum for my question, but it's the cloest I could find.

I'm using NoteTab (notetab.com) to do some html coding. In the Help menu, it says: Those familiar with UNIX text utilities will find that the engine is somewhere between EGREP and AWK with regard to the complexity of problems that it can solve.

Basically, I have 12 pages that I would like to error check using regular expressions. I've only used RE sparingly, so I'm not sure how to construct the statment.

What I would like to do is find instances of the following group of code where the X's are not the same:

A<input type="radio" value="A" name="X">
B<input type="radio" value="B" name="X">
C<input type="radio" value="C" name="X">
D<input type="radio" value="D" name="X">

I have around 2500 radio button groups and would like to avoid checking them one by one. Any help would be greatly appreciated. Also, sorry if this is in the wrong place. Thanks!

grep "[A-Z]<input type=\"radio\" value=\"[A-Z]\" name=\"[A-Z]\">" filename

Here filename contains the data to be searched for