It sounds like you've done what would be immediately logical, but are misunderstanding some concepts to diagnose the problem. If could be that the HFS code in the kernel is no-longer working, but its more likely there is a problem with your disk, or the permissions needed to access it.
So apologies if this is too basic but.. Firstly the whole disk, is really just a blob of data. Normally that starts with a partition table, which then defines subsections of that blob of data, which are then 'formatted' according to a certain standard.
Regardless of what the format of the disk is, you should be able to either copy the entire 250Mb Blob, as a straight blob of data, to a modern disk, or identify which partitions are important, and copy those as separate blobs.
Mounting a partition, essentially means having the OS, use the blob, actually in place on the original disk, whilst understanding the format of said blob.
Most of the work I did with HFS and HFS+ partitions, started with copying the entire disk to a file, then working with that file.
You haven't really given enough information for my to give you specifics, but here's what I'd do in your situation.
First get a linux machine running, either natively or using a recovery disk (such as you get with any Ubuntu Desktop install CD).
Next install drivers for and mount a target disk, where you intend to put your HFS image. This could be an actual install HDD, a USB stick, or a remote file share (even a windows box, with an smb share would work).
Next look at the list of partitions available on the box, by running cat /proc/partitions
Next plug in your HFS drive via USB, give it a sec, and run cat /proc/partitions, and play spot the difference, to see if/where the new disk appeared.
The disk might be called /dev/sd[a-z] or /dev/hd[a-z] (where the [a-z] could be any letter), or it might have detected partitions, so given you /dev/sd[a-z][1-9] (where the [1-9] is the partition number it's seeing).
Once you have identified the partition(s) you want, copy them to a file, on the partition we mentioned earlier (see https://stackoverflow.com/questions/30048316/is-it-safe-to-backup-a-partition-with-dd/30048462). So if that was /dev/sda1 and /volume1 the command might be something like dd if=/dev/sda1 > /volume1/sda1_hfs_image
Now the act of making a copy of the image, should address all the permissions issues I said might be the cause of the problem. It'll also fail if the disk is physically corrupt.
Once you have the image, then you should be able to install the hfs modules, and simply mount it using mount -t hfs /volume1/sda1_hfs_image /mnt. From memory though hfsutils would just access the filesystem in a terminal, rather than mounting it.
It's been nearly 20 years since I last played with HFS (around the time OS X came out), so I'm a bit rusty (I saw your cry for help linking to this question on the hfs-user@ mailing list, so it's not totally ignored)
Regards,
Si
