I personal use offlinelist, but if you have a slot one flashcart you could always use rominator i believe. You can find out more about that by searching the forum.

 

I am not sure if you are asking for a DS side application for renaming or a PC one.

DS side
There is an application aimed at renaming (edit) viewing roms. My bad.
http://gbatemp.net/index.php?showtopic=82895&hl=
There are several apps aimed at renaming files in general and there is DSlinux as well (which has a unix command line with all that it entails).

PC side
Bridgy84 is correct, there are loads of apps aimed at renaming roms.
rominator is a common one
http://www.rominator.net/

Offline list. There is an official dat as I recall but most stick to ADVANsCEne or no-intro for naming lists.
http://offlinelist.free.fr
http://www.advanscene.com/
http://nointro.free.fr/ and http://www.no-intro.org/ no-intro also support dats for the DS for several other slightly older apps.

ADVANsCEne also have their own and/or host forums for two others called ndscrc and rtoolds
http://www.advanscene.com/

There was a java one called rofage released a few months back:
http://code.google.com/p/rofage/

A note, you mentioned checksum. If you trimmed the roms or patched them in some way the checksum will not match that in the list. There are a few that rename according to the header though.

 

Thanks!

Rominator did the job, but I wil defenitely check offlinelist.