5
If you refer to logo, then you can edit the image file which is located in the image directory of the theme:
xoops/themes/theme_name/images
If the size of the image is specified in the html code (and you want to change the image size), then you need to look at editing the theme.html file should you wish to change the hard code size. Not all themes hard code the image width.
If you refer to the banners, then in the admin of xoops, you can turn banners off
admin
- system module
- preferences
Or you can remove XOOPS as a client and add your own banners
admin
- system module
- Banners
Hope this is of help