Got BIG file (1,195,903 kb) on one disc This doesnt seem a very big file in the end, most dvd's should hit about 4,200,000 odd, which is why its probably pixilated a lot, unless the 1,195,903 the size on the avi file, which would also explain the pixelation as well, i.e the avi file must be a long film. A rough guide is a 90min film you can use around 6000kbit for encoding.
As for the audio and video sync problem, yes, this is a very common problem, with aquired avi files. Can this be fixed? Yes, but it isnt easy, per say, verging on complicated.
Here goes: you require a program called Virtualdub http://www.virtualdub.org/, download, unzip to a folder and run the program. Now open your avi file with this program, if theres an error in the audio track it will tell you upon opening the avi file, you can use "file info" which tells you the codec for video and audio, if its unknown it will display tag2000 or tag something. Now use "save wav" and it will extract the audio track only. You now have avi file and a wav file, you will have to re-combine these togeather so that the original avi file audio track is removed and is replaced by this wav version. This corrects 99.99999% of all audio/video sync problems.
Now comes the hard part, getting Nero to accept this new audio track, there was alot of swearing involved here, its not designed to do this "properly", sort of, i'm not exactly sure why it does this, you may have more success, than i had. You have to use the "make movie" option instead of "Make dvd", then use the "browse" button and add the avi file, browse again and add the wav file, now drag and drop the avi into the "video track" part, drag and drop "wav" into "audio track 1", then hit next, then alter any kbit rate etc. Use the "make movie" from within the "make dvd video" option, if you use it directly from nve3's main menu, it crashed when you use next buttton You should, when this has finished a dvd with a new audio track or one that has 2 audio tracks, as i havent tested this.
These may help:
http://www.ahead.de/en/Tutorials_Vision_Express_2.html Same as vesion 3 i belive
Unfortunalty i cant help much beyond this, as i dont ever use this program any more or ever used it, this is not to take anything away from Nero, its just not got such an easy way of dealing with this, but ask anyways. I use TMPGENC Plus, which is very easy for avi files, add avi file, add your wave file, hit next twice, change kbit rate and encode away. Obviously not the cheapest program around, but its results are very good. Then you can use nero to create menu etc.