It used to be that public domain, Type 1 fonts were much poorer quality than Computer Modern bit mapped fonts. This situation has improved in the last several years, though, but matching the fonts is up to you. Having several different font systems on one machine can seem redundant and an unnecessary waste of disk space. And the Computer Modern fonts can seem, well, a little too formal to be suitable for everyday use. It reminds me sometimes of bringing out the good China to feed the dog. At least you don't need to spend a bundle on professional quality fonts any longer.
One of the major improvements of LaTeX2e over its predecessor was the inclusion of the New Font Selection Scheme. (It's now called PSNFSS.) Formerly, TeX authors would specify fonts with commands like
\font=bodyroman = cmr10 scaled \magstep 1
which provides precision but requires the skills of a type designer and mathematician to make good use of. Also, it's not very portable. If another system didn't have the font cmr10 (this is TeX nomenclature for Computer Modern Roman, 10 point, with the default medium stroke weight), somebody would have to re-code the fonts specifications for the entire document. PSNFSS, however, allows you specify fonts by family (Computer Modern, URW Nimbus, Helvetica, Utopia, and so forth), weight (light, medium, bold), orientation (upright or oblique), face (Roman, Italic), and base point size. (See the section Characters and type styles for a description of the commands to specify typefaces.) Many fonts are packaged as families. For example, a Roman-type font may come packaged with a sans serif font, like Helvetica, and a monospaced font, like Courier. You, as the author of a LaTeX document, can specify an entire font family with one command.
There are, as I said, several high-quality font sets available in the public domain. One of them is Adobe Utopia. Another is Bitstream Charter. Both are commercial quality fonts which have been donated to the public domain.
These happen to be two of my favorites. If you look around one of the CTAN sites, you will find these and other fonts archived there. There are enough fonts around that you'll be able to design documents the way you want them to look, and not just English text, either. TeX was originally designed for mathematical typesetting, so there is a full range of mathematical fonts available, as well as Cyrillic, Greek, Kana, and other alphabets too numerous to mention.
The important thing to look for is files which have either the .pfa or .pfb extension. They indicate that these are the scalable fonts themselves, not simply the metrics files. Type 1 fonts use .pfm metric files, as opposed to the .tfm metric files which bit mapped fonts use. The two font sets I mentioned above are included in teTeX distributions, as well as separately.
What I said above, concerning the ease of font selection under PSNFSS, is true in this instance. If we want to use the Charter fonts in our document instead of Computer Modern bit mapped, all that is necessary is include the LaTeX statement
\renewcommand{\familydefault}{bch}
in the document preamble, where ``bch'' is the common designation for Bitstream Charter. The Charter fonts reside in the directory
/usr/lib/teTeX/texmf/fonts/type1/bitstrea/charter
There you'll see the .pfb files of the Charter fonts: bchb8a.pfb for Charter Bold, bchr8a.pfb for Charter Roman, bchbi8a.pfb for Charter Bold Italic. The ``8a'' in the font names indicates the character encoding. At this point you shouldn't need to worry much about them, because the encodings mostly differ for 8-bit characters, which have numeric values above 128 decimal. They mostly define accents and non-English characters. The Type 1 font encodings generally work well for Western alphabets because they conform to the ISO 8859 standards for international character sets, so this is an added benefit of using them.
To typeset a document which has Charter fonts selected, you would give the command
pslatex document.tex
pslatex is a variant of teTeX's standard latex command which defines the directories where the Type 1 fonts are, as well as some additional LaTeX code to load. You'll see the notice screen for pslatex followed by the status output of the TeX job itself. In a moment, you'll have a .dvi file which includes the Charter font requests. You can then print the file with dvips, and gs if necessary.
Installing a Type 1 font set is not difficult, as long as you follow a few basic steps. You should unpack the fonts in a subdirectory of the /usr/lib/teTeX/texmf/fonts/type1 directory, where your other Type 1 fonts are located, and then run texhash to let the directory search routines know that the fonts have been added. Then you need to add the font descriptions to the file psfonts.map so dvips knows they're on the system. The format of the psfonts.map file is covered in a couple different places in the references mentioned above. Again, remember to run the texhash program to update the teTeX directory database.
It is definitely an advantage to use the X Windows System with teTeX--- XFree86 under Linux---because it allows for superior document previewing. It's not required, but in general, anything that allows for easier screen previewing is going to benefit your work, in terms of the quality of the output. However, there is a tradeoff with speed of editing, which is much quicker on character-mode displays.