flat assembler - Boot an image from DOS

Hi, I need some help in booting a raw image from DOS mode.
What I mean, I try to make simple DOS COM/EXE executable file which should read a raw CDROM bootsector at 0000:7C00h and run it. But when I run it, it hangs!
As I see, there's many interrupts & other mess which DOS should restore when booting to int 19h, but it doesn't!

Code:

        mov     ax, cs
        mov     ds, ax
        mov     dx, new_int
        mov     ax, 2519h
        int     21h  ;  set new int 19h handler

        mov     dx, fname
        mov     ax, 3d00h
        int     21h  ;  open file
        jc      error
        mov     [fhandle], ax

        mov     bx, ax
        mov     cx, 0800h
        mov     ax, cs
        mov     ds, ax
        mov     dx, 0200h
        mov     ah, 3fh
        int     21h  ;  read file to CS:0200h
        jc      error

        int     19h  ;  reboot to new handler

error:
        mov     ax, 0900h
        mov     dx, error1
        int     21h
        mov     ax, 01h
        int     21h

new_int:
        cli
        mov     ax, cs
        mov     ds, ax
        xor     ax, ax
        mov     es, ax
        mov     si, 0200h
        mov     di, 07c00h
        mov     cx, 0800h
        rep     movsb

        mov     dx, 00e0h
        jmp     far 0000h:7c00h


noerror db 'File open success!$'
error1 db 'Error opening file!$'
fname db 'no_emul.BIN',0
fhandle dw ?

This piece of code says "Press any key to boot from cd.." and when the key is pressed, hangzZz...

P.S. I try to boot a win installation from DOS. Could it be better loading SETUPLDR.BIN than original no_emul_boot.img from XP CD ?