Wasn't very expensive, just over 100 euro's for a 64GB version.
The interesting part would be moving Windows over to the new disk. Haven't had good experiences with moving windows. Absolutely not worried about moving Linux around, never had problems with that :)
So using ntfsclone I migrated the ntfs partition to the other disk (made partition table first of course). Connected the SSD to the notebook with a USB adapter. Original XP installation is on hda1 and has to be migrated to sda1.
After waiting for a while the migration was done.
Rebooted the system into single user mode and moved linux over.
Then the hardware part, opening the MSI. Done it times before on this notebook, it isn't too difficult.
Then take out the old harddisk.
I replaced it with the SSD. Didn't close up the notebook directly, but first connected it to power to see if it would boot at all. And it did, including windows :) ntfsclone seems to work really well for this kind of thing.
Everything seems to work really well. Notebook feels a bit more snappy and is a lot more quiet :)