Hello bruno,
I have several older machines with similar specs to you (do you only have 150Mb RAM?) and prefer the text installer anyway.
For my initial installation of Vector I always partition the same way:
Using cfdisk :
1. "Delete" all the old partitions (select with arrow and press enter on Delete)
2. "Create" a swap partition twice the size of my RAM
3. Then "Create" a root partition of about 5Gb
4. "Create" a Home partition of the rest of the HD
5. Go back and select each partition and using "Type" select 82 for swap for the first, and 83, Linux, for the other two partitions.
6. Select the second partition and toggle the "Bootable" switch
At this stage cfdisk should be vaguely (from memory) like this:
hda1 Primary Linux swap Swap 558 Mb
hda2 Boot Primary Linux / 4358
hda3 Primary Linux /home 4998
7. "Write" it to the disk
8. Reboot
9. As you install, you will be prompted to select hda1 as your Swap partition, hda2 as your Root partition and you will be asked if you want to select additional partitions so choose Home for hda3.
10. I user Reiser filesystem when formatting root and home
That is it.
The reason for having a separate Home partition is that when you install the next version of Vector, you will not have to reformat the Home partition and all your data is still there on the disk when you log into the new version.
Hope this helps