Yeah the top left and top right ones seem to be differently sized versions of the same font- both had kiaro in the name.
Generally though
You need to get the files out of the rom. There are almost countless tools to do this- I probably used
crystaltile2 but
ndstool,
ndsts,
tinke and
nitro explorer are just a few of the tools that can parse the DS file system. Most of those are fairly obvious or include some usage on the links (for crystaltile2 click on the little DS icon that should be around the right of the menus and icons and then when you find the file in the new windows right click).
Either way you want to go to the data\font directory. If you decompress with ndstool it will make a data directory for everything other than the overlays and binaries so the directory will in fact read data\data\font\
There are a bunch of files with the extension .dat but they are compressed with the rarer/newer type 40 compression (tinke probably does though). So grab them and then you will need to feed them to a decompression tool.
As mentioned the compression is somewhat newer than many tools which includes crystaltile2 but the lzx program from
CUE's GBA/DS compressors* (
filetrip link) and
DSdecmp are a couple of the tools that can handle it and most other compression methods seen on the DS (certainly all the common ones and there is so very little custom stuff these days). They are command line for the most part but fairly simple to use.
After this you need something to parse the NFTR font format for which you have a few options. Some are will parse the file anyway but if you can give the files the nftr extension if it did not have it already that would be good. I suspect the one you want is "kiaro1010.nftr".
NFTR editor (
filetrip link is what I used for the original reply. You can open it in it and then click on the tools dropdown menu or file dropdown menu -> dump tiles (and be given the option of to bitmap or to clipboard) which is what gave that final image.
tinke
If you are playing along with it you probably would not have had to leave the program as it can handle everything done today- parse filesystems, handle type 40 compression and view/edit NFTR fonts.
crystaltile2 has abilities here as well.
As for the last question I do not know any tools to convert fonts and the ones I had a go with aiming to trace them by hand were not very stable; fonts on computers this side of the early 1990's at the latest are vector graphics by nature and have a whole lot of additional info (which actually NFTR does have but nobody has really made export options that would be useful to conventional font making) where these are bitmap fonts. Font making is as much a skill as image editing, video editing, audio composing and audio mastering and I am afraid I just about know the basics of how fonts work (on a good day I might be able to recall most of http://freetype.sourceforge.net/freetype2/docs/glyphs/Image3.png ) so I will have to defer to others.
*a little batch file to get Cue's tools working and produce uncompressed files named nftr. It should not matter if you do not have all the files, basic usage is paste the codebox section into a text file and save it with the extension .bat , stick it in the same directory as the fonts you grabbed with whatever and also stick the lzx.exe from Cue's tools in there before double clicking on the .bat file and then it will run doing it all for you. If you really want ndstool could be added in as well and snatch the files from the rom but it is probably best if you know how to grab files from the DS filesystem.
Code:
lzx.exe -d kiaro0808.dat
lzx.exe -d kiaro0808slim.dat
lzx.exe -d kiaro1010.dat
lzx.exe -d kiaro1212.dat
lzx.exe -d kodaigo.dat
lzx.exe -d lc0808.dat
lzx.exe -d lc1010.dat
lzx.exe -d lc1212.dat
lzx.exe -d nakrubi0606.dat
lzx.exe -d nakrubi0606_slim.dat
rename kiaro0808.dat kiaro0808.nftr
rename kiaro0808slim.dat kiaro0808slim.nftr
rename kiaro1010.dat kiaro1010.nftr
rename kiaro1212.dat kiaro1212.nftr
rename kodaigo.dat kodaigo.nftr
rename lc0808.dat lc0808.nftr
rename lc1010.dat lc1010.nftr
rename lc1212.dat lc1212.nftr
rename nakrubi0606.dat nakrubi0606.nftr
rename nakrubi0606_slim.dat nakrubi0606_slim.nftr