Hi tomipetteri,
The following work for me:

a) for qt based applications, you should install Qt4-dev:

$su: => password
#tazpkg get-install Qt4-dev

Then login as Tux user (need to do it for every user) and run 'qtconfig' on terminal. A graphical interface will open and you will be able to configure the font under tab "Fonts". Really easy.

b) for gtk based applications, just click on red spider on your x window and then choose 'preference-apparence gtk-font' and then adapt the font to your need. Really easy as well.

c) to change the text console font (xterm), you need to edit the file: ~/.Xdefaults and adapt the following line to your need with your preferred text editor (I use vi):

$~vi ~/.Xdefaults
xterm*faceSize:  11   <== edit this line to your needs.<br />

d) I you use firefox ( I don't), just edit the file ~/.mozilla/firefox/xxxx.../chrome/userChrome.css and change the line:

$~vi ~/.mozilla/firefox/xxxx.../chrome/userChrome.css
font-size: 14pt

Hope this helps.
Cheers.
Stephane

Thank you Totoetsasoeur,

I have managed b) and c) and d) in a way (there was a min font size box for midori)
The main problem as now is a). I’m assuming qt based applications are the applications like ‘Wireless wizard’, ‘configure network’ etc?

I did:
****

tux@slitaz:~$ su
Password: *****
root@slitaz:/home/tux# tzpkg get-install Qt4-dev
% everything seemed to go well)
%SliTaz asks my username: in an graphical window
Username: tux
Passwrd: ****
%I open shell and type:
qtconfig
%I also tru su qtconfig
%It says
qtconfig not found

*****

I have not installed SliTaz to hard drive, is that the reason? If this is the case any ideas from where to find install tutorial (shell install) ?

Dear Tomipetteri,
All I spoke about was for Slitaz installed on HDD. I have no idea if cd-live should give the same results.

Anyway here are some hints (once again related to slitaz on HDD) that may help you:

If you think that Qt4-dev installation was ok and you still cannot access to qtconfig bin file, I think either installation process was not successful or your $PATH is not up to date (I am far away of being a Slitaz guru and might be completely wrong...).

Firstly would you please check if qtconfig is really available with:

~$ ls -l /usr/bin/qtconfig
-rwxr-xr-x 1 root root 229300 May 27 08:57 /usr/bin/qtconfig
~$

Then either qtconfig is present => a), or is not => b).
a) If file qtconfig is present, then your $PATH was not updated. Lets check the $PATH:

~$ echo $PATH
/usr/sbin:/usr/bin:/sbin:/bin
~$

b) If file qtconfig is not in /usr/bin, then something went wrong with the installation. You should try to investigate to find out. Check the logs, receipt, etc... If you do not find why, here is a small work around that will allow you to work:
- create a new file called Trolltech.conf in directory ~/.config (need to create one for every user),
- and put the following in it (for info, the number 12 is the font size):

~$ vi ~/.config/Trolltech.conf
[Qt]
font="Sans Serif,12,-1,5,50,0,0,0,0,0"

Comment: there are 2 lines in this file.

Happy Slitaz
:-D
Stephane

PS:
Moreover here is the howto for HDD installation:
http://doc.slitaz.org/en:handbook:installation