Why not have SystemRescueCd instead of Parted Magic? SystemRescueCd has a lot of tools already categorized by the UBCD menu. SystemRescueCd I beleave has more tools then the Parted Magic.

I see they have a lot of same programs and Parted magic just has more GUI. Though would be nice to still offer a version with it.

SysRescueCD is too big. It's about 200MB. Parted Magic is only 45MB, and already UBCD V5b3 is running at 200MB total!

What other usefull tools dose Parted Magic have for windows users?

See: http://partedmagic.com/wiki/PartedMagic.php?n=PartedMagic.Programs

Some usefull utilities:

GParted -partition editor that uses libparted (can resize and shrink partitions without loosing your data)
ddrescue -does not abort on errors on the input file (can copy data of a damaged hard disk to a new hard disk)
myrescue -rescue still-readable data from a damaged harddisk
partimage -utility which saves partitions to an image file (Harddisk Image Cloning utility)
PhotoRec -digital photo recovery (can also recover files from a hard drive when the filesystem is damaged)
TestDisk -partition scanner and disk recovery tool (e.g. reconstruct partition table, write new MBR, ...) ==> (this utility has rescued me several times)

Why not slax linux as it allows adding modules like UBCD dose? It is a version of linux designed to be small and powerfull. http://www.slax.org/

What does slax have when you boot it?
Does it have: GParted, ddrescue, myrescue, partimage, photorec, testdisk, ... other usefull recovery tools?

I think Slax is more a small desktop system, not a rescue/partiton system.

I think that Victor also find it to big (189MiB).

It seems a nice distro to me, but I think it is not suitable for the goal of UBCD. You can probably easily include it yourself because it probably will also use isolinux.

Parted Magic size is 44 MiB (4 times smaller). We can extend it with antivirus software and other tools if we want. Make a 7zip archive of the files that the program needs and place it in /pmagic/pmodules

See the antivirus topic for examples of the 7zip archives, It is made for Parted Magic 2.2. In the new version of Parted Magic 3.0, the files should be inside a /usr folder first, because it unpacks the files in /. Parted Magic 2.2 unpacks files directly in /usr.
http://www.ultimatebootcd.com/forums/viewtopic.php?t=1361

All the tools you asked about can be added as Modules. It is 189mb though. Never mind then, it was just a though. I typicaly use a full blow distro live CD to make my needed Linux tweaks. I am excited about parted magic as part of UBCD though and will be excited when it's no longer a bata.