For Linux too!
There are excellent CD-burning utilities for the Linux GUI; X-Windows :
k3b in KDE, http://freshmeat.net/projects/k3b
gnomebaker in GNOME,
brasero in GNOME, http://www.gnome.org/projects/brasero/
Even better is the standard cdrkit/cdrtools 'cdrecord' command in Linux .
Info on this command-line command is at the DLS Burning a Bootable CD page, http://www.damnsmalllinux.org/wiki/index.php/Burning_a_Bootable_CD
And excellent documentation on both cdrecord and the mkisofs ISO-remastering commands is at http://www-128.ibm.com/developerworks/linux/library/l-cdburn.html
I've had consistently excellent results once the UBCD ISO is mastered correctly, via the commend sequence
cdrecord -v -eject speed=8 dev=x,x,x ubcdxxxx.iso
where x,x,x are the device numbers of my specific CD-RW device found through cdrecord -scanbus, and ubcdxxxx
is the specific UBCD ISO variant to be burnt into a bootable CD.
End-note here: 'cdrecord' sure seems to be the
straightforward and tried-and-true one for some of us Linux commandline buffs!