Hi everybody, i need help regarding my Linux start up.I was trying to configure internet connection with my Red Hat in order to use for Internet,but of no avail and I think I have changed one parameter to activate device during computer start up.

Now the problem is during start up and filesystem checks it hang, in this portion "Bringing up interface ppp0. and nothing happening I can't open my Linux anymore.

Please help...Thanks...

Check:
/etc/sysconfig/networking/devices/ifcfg-ppp0
make sure that ONBOOT='yes'
is changed to no.
you may access the system by booting from the install cd, and either typing rescue, or just hit enter, and answer the questions reguarding keyboard type/locale, then press alt+cntrl+F3 to switch to a terminal. Then type:
mkdir foobar
mount /dev/hdax /foobar
chroot /foobar
where hdax is the name of the root partition. you chroot, so you can use your own editor, some boot disks dont have vi for instance. then, you can type:
vi /etc/sysconfig/networking/devices/ifcfg-ppp0
and change that line. for vi, press I, then scroll to the line, then edit it, then hit escape, and :wq
that should work.