2 files to 1

I have just ripped Hellboy from the DVD to a winamp media file… but it made it into two different files one thats 729Mb and another that 128Mb. how can i get this to one file?
I ripped it to a IFO file with smartripper then went to a VCD(MPEG1) with No1 Dvd ripper SE.

What I’ can use

#1 DVD Ripper SE 1.3.30
Smart Ripper 2.41
Alcohol 120% 1.9.2 (1705)
WinXP SP1 (2600)
Lite-On LTR-5237s
Samsung CDRW/DVD SM-308B

use neronesion expess to insert both files, selct them both and then click “merge” then export back to avi, or you couls use virtualdub.

Use TMPGEnc MPEG Tools Merge option to join the two files without having to re-encode.

and where would i get a hold of those programs?

Grab TMPGEnc 2.521
Once installed, run.
Close the wizard if it pops open.
from File Menu select MPEG Tools.
From the tabs at the top select Merge/Cut
Add your MPG files in order (make sure MPEG-1 System or MPEG-1 VideoCD is selected)
Give the file a name (browse to folder location)

My prob is quite similar, but my files are *.avi format.
Tmpgenc doesn’t work with them. Which program may i use to merge them without re-encode?