SUCCESS !
I've been able to use GK correctly now, well, it seems like it's working. I've made some test, and I think I got it. Looks like it's deinterlaced, and the fps are at 23.97. The only thing is, it's a .avi (XviD), not a .mkv, cause I couldn't do a .mkv in GK, it gave me an error, so it was impossible to make one. Anyway, the .avi look really good ! I've choosed the 1/3 DVD setting, to get the most of it. Here's the spec, and if it's alright with you, i'll do the other four disc...
Format : AVI
Format/Info : Audio Video Interleave
File size : 1.46 GiB
Duration : 1h 35mn
Overall bit rate : 2 183 Kbps
Writing application : VirtualDubMod 1.5.10.2 (build 2540/release)
Writing library : VirtualDubMod build 2540/release
Video
Format : MPEG-4 Visual
Format profile : Streaming Video@L1
Format settings, BVOP : Yes
Format settings, QPel : No
Format settings, GMC : No warppoints
Format settings, Matrix : Default
Muxing mode : Packed bitstream
Codec ID : XVID
Codec ID/Hint : XviD
Duration : 1h 35mn
Bit rate : 1 725 Kbps
Width : 640 pixels
Height : 352 pixels
Display aspect ratio : 16/9
Frame rate : 23.976 fps
Resolution : 24 bits
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.319
Stream size : 1.15 GiB (79%)
Writing library : XviD 50
Audio
Format : AC-3
Format/Info : Audio Coding 3
Codec ID : 2000
Duration : 1h 35mn
Bit rate mode : Constant
Bit rate : 448 Kbps
Channel(s) : 2 channels
Channel positions : L R
Sampling rate : 48.0 KHz
Stream size : 306 MiB (21%)
Alignment : Split accross interleaves
Interleave, duration : 42 ms (1.00 video frame)
Interleave, preload duration : 500 ms