[newbie] Boot manager problem???

[Ameya Naik]

Hi ,
I installed linux on a machine with 20 GB HDD.
I had configured lilo while installing but it doesn't show up during
boot.
It gives an error that there are more than 1024 cylinders or something
like that.
How do i solve this problem?
Also can anyone tell me that if i want to use Grub as my boot manager,
How do i configure it? I have never used it, so please tell me the
procedure from the beginning...
Thanks
Looking forward for some responses........
Bye,
Ameya....