First, you should learn difference between chainloader and bootloader, and how all those OSes you have installed boot. Second, if you "ain't got time" stick to Windows. UNIX requires time, will and patience.
i'm going to install on first hole(where is xp) (archlinux is on 2nd)...no inconvenient with freeBSD boot-manager?
Don't install FreeBSD boot manager. Your GRUB can boot FreeBSD from UFS partition.
what to choose[the best] on installation: UFS or ZFS and which de/wm with 256 mb ram,2.26 ghz processor intel P4?
You can't choose anything of that kind @ installation. You will get UFS partitions inside a FreeBSD slice with only base system, that lacks any form of GUI. ZFS requires manual installation (and that requires skills you'll never get if you don't change attitude), and 256MB ram on i386 is a no-go for that filesystem.
what to choose: 8 stable, 8.2 release?
I generally prefer -STABLE branch on desktop because of faster code updates and up-to-date packages which -RELEASE repository lacks. For -RELEASE, packages are compiled only when that particular version rolls out, receiving only security patches. For -STABLE, clusters are compiling new versions of packages. You can use -STABLE repository on -RELEASE system by setting a few environment variables. That's not problematic but it isn't recommended, either. -RELEASE systems can be upgraded to new minor or major versions via binary upgrade tool. -STABLE can be only re-built. Meaning that you need to fetch the complete system sources and compile "world". That can take a while on 2.26 P4.
This is all written in the handbook. You're asking us to type again what's already been written in official documentation. Because of your laziness to "read long manuals". I'm not responding to your general questions any more - go RTFM.