There are some typescripts for usual fonts in your ConTeXt distribution. But
they seldom seem to work. It's better to make your own new metrics and
typescripts.
USING EXISTENT FONTS AND TFM METRICS
--- file: type-mine.tex ---
% this maps the font name to the TFM file name
% (here: free URW "Times")
\starttypescript [serif] [times] [texnansi]
\definefontsynonym [Times-Roman] [utmr8t] [encoding=texnansi]
\definefontsynonym [Times-Italic][utmri8t][encoding=texnansi]
% etc.
\stoptypescript
% this maps Serif to the specific font
\starttypescript [serif] [times] [name]
\definefontsynonym [Serif] [Times-Roman]
\definefontsynonym [SerifItalic] [Times-Italic]
% etc.
\stoptypescript
% tell pdftex to load a map file
\starttypescript [map] [texnansi]
\loadmapfile [texnansi-urw-times.map]
\stoptypescript
\starttypescript [mine] [myset]
\definetypeface [myset] [rm] [serif] [times] [default] [encoding=texnansi]
% and similar for ss/sans, mm/math, tt/mono fonts
\stoptypescript
--- end ---
--- file: mydoc.tex ---
...
\setupencoding [default=texnansi]
\usetypescriptfile [type-mine]
\usetypescript [mine] [myset]
\setupbodyfont [myset,rm,12pt]
...
--- end ---
INSTALLING NEW FONTS
You need: Font binaries: PFBs or PFAs
Font metrics: AFMs
Installed tools: AFM2TFM, VPtoVF, PLtoTF
--> see also mtexfont.pdf and mfonts.pdf!
1. copy all PFB/PFA and AFM files of one family to your "other" TeX root
2. call the texfont script:
texfont --ve=vendor --co=collection --en=encoding --fo=fontroot --in --ma
e.g.: texfont --ve=adobe --co=palatino --en=texnansi
--fo=/usr/local/texmf-var --in --ma
This copies the files to the appropriate directories, makes TeX metrics,
virtual fonts, a pdftex-mapfile and a test file (enc-vendor-collection.tex).
I'd suggest to repeat it with "all" encodings that you could need (ec, 8r).
3. write typescripts like above. you can copy some lines from the test files,
but replace every encoding (texnansi in the above example) with
"\defaultencoding".
4. use it in your docs like above
HTH
Gr��lis vom Hraban!
Greetlings from the Raven!