Can somebody tell me if it is possible to change a film format from Svcd to just Vcd as some dvd players have a problem playing Svcd format.
Yes, it is perfectly possible, but quality _will_ suffer -- it will be MUCH worse than what it would be if you would convert DVD directly to VCD (because you've already done lossy encoding once when you encoded the SVCD). Good thing is that audio doesn't need to be re-encoded. Simply demux the audio and video to separate files with TMPGEnc's MPEG Tools. Then re-encode the SVCD video clip you got from demuxing process (.m2v) into VCD. Select correct TMPGEnc template according to your SVCD's fps (PAL, NTSC, NTSCFilm), change "motion search precision" into highest, select correct aspect thingys and encode the clip. Then simply remux the resulting .m1v file and the audio what you demuxed originally (.mp2) into .mpg and burn it with Nero.