Disk upgrade problem

[glow2797 at bigpond.net.au]

Having a problem upgrading a hard disk with RH 8.0 and an AMD 800 processor and looking for suggestions.
Have seen a posting on this list which might relate but can't find it now!

Bought a Seagate Barracuda 200G drive

Followed document from the Linux documentation project at
www.tldp.org on Hard disk upgrade. Basically tells you to 
1. Install new with old
2. Partition new like the old.
3. Format new disk partitions.
4. Mount new as /new-disk.......
5. Copy files from old to new
6.....Talks about lilo after this but I have grub installed.
7. Take out old disk, make new disk master and reboot.

Done all this stuff and tried to boot but wouldn't start, kept failing at "Verifying DMI Pool data" which is just before grub is activated.
Searched internet and found that I might have a 137G problem. Only have an AMD Duron 800 installed. Went back to shop and changed for a 120G drive, have went through the process again and find am getting same problem? 
Installing 200G drive the BIOS was reporting a 137G capacity on drive but this time BIOS is reporting properly. 

Seen a posting here which mentioned something about formatting initially with DOS as the disk size etc is contained in a block on the disk which is passed to Linux and this struck a cord as when I look at old fdisk I have an extended partition at dev/hda4 (root directory is mounted on /dev/hda5) which is reported as type Win95 extended. Previously this was installed using the cdrom disc set so I had minimal knowledge of the settings, however I have assumed this is mistake as could tldp document does not mention this and I can't find how to set it as this. 

Any tips, or is there any way I can pin down what problem is, have lost a bit of hair over this so thanks for any help.

Gordon Low