When trying to burn avi files to vcd using nero the files become bigger and no longer fit onto the cd is there any way round this, 
change them to mpeg
encode to mpeg or get tmpg with xvid template then run the file threw tmpg burn threw nero burning rom “non compliant” it will look almost dvd,if not full quality
I know one which is easy to use and has good quality. That is Total Video2Dvd.
It is it can converts any High-Definition video formats such as HD-DV, MKV, Blu-ray TS, TP, M2TS, AVCHD, WMV-HD, HD avi to DVD and all other popular video formats Youtube FLV, Xvid avi, Mov, Rmvb, Rm, Divx, Wmv, Asf, VOB, DV, 3gp, Ogm, Mpeg, Mpeg4, AVI to DVD formats.
http://www.effectmatrix.com/total_video_to_DVD_Author/index.htm