Hi folks!
Solved the damn issue! Here's how (you will need some spare HDDs...):
1. Fresh, clean Win XP install on a spare HDD
2. Boot Win XP with an similar, good HDD (let's call it
HD1) as the bad one (let's call it
HD2) attached on SATA port (IDE mode in BIOS)
3. Hot swap
HD1 with
HD2 (this one made me a little nervous

)
4.
WDMarvel - apply "Slow Responding" fix
5. Shutdown the PC, place again the
HD1 on SATA port and attach a third - destination - HDD (
HD3)
3. Boot Win XP and hot swap again
HD1 with
HD2 (this time I was about to pass out

)
5.
DMDE - copy from
HD2 to
HD3 all the stuff (over 95% of files recovered)
6. Have a lot of beers!
Yes, it will cost you about 30 EUROS, but it will worth every cent! Thanks
Spildit,
WDMarvel and
DMDE!