Delete specific files using Command Scripting

[brat33]

I have lots of files that need monthly cleanup done on them. These files are located in many different directories on the same server. Some example files names are C1234.idx, C1111.idx, C8693.idx, etc....ALL the files will start with either an 'C' or an 'L' and then contain 4 random numbers followed by an extension of either .idx, or .dat. The problem is that there are also files named CTFIX.idx, Ctons.idx, etc...So I can not use:

DEL ServerName\PathName\C????.idx 

as then all files that are 5 characters in length starting with C will be deleted and I only want to delete files that start with C and have numbers following.

DEL ServerName\PathName\C****.idx  

as then all the files starting with C will be deleted.

Is there anyway to delete specific files that point just to numeric characters? If not, does anyone have any suggestions on how I may go about deleting these files using another language?

Thank you in advance!!!

Amy