Can anybody help me?????

I don't quite understand your questions.

Please be clear about:

A. Your source footage - is it still pictures (jpg), or is it video, if so, what sort of video and how was it captured?

B. How are you trying to output after editing - back to DV Tape, MPEG2 for DVD etc?

Well, thanks Peter for taking time to respond. As a newbe, I guess I am almost making it. Let's make it more concise, ok?
In one of my posts, JohnnyRoy told me how to join 2 projects - let's say project 1 and 2 - (Ctrl + A; Ctrl + C and Ctrl + V....etc...). After that, I name the new file as project 3 (both 1 and 2 are made up with efects, still JPEG files, and wav files (each one with its own wav file). When I render the whole project 3, (if I'm doing the right thing), I go to the menu, FIle, Render as and choose the options I want (for instance, MPEG1). This procedure works for MPEG1 and wmv files (if this is the right procedure) because in this case, video and soundtrack play perfectly. As soon as I try to render again the whole project 3 (which is made up of 2 projects, remember?) as AVI or MPEG2, I've got excellent video, but the soundtrack does not match the video, I mean, there's a kind of delay for the video (when u insert another audio file and record to make all wav files form each project as one, you can notice perfectly that the generated file is bigger than the whole project. Even if I try to render both files as AVi or MPEG2 (project 1 and project 2, separetly) and later re-rendering them this way (File; Render as), it happens the same thing.

Reading Vegas help, I've noticed they advice how to make video compositing..."From the Tools menu, choose Render to New Track to mix multiple tracks to a single track. This function is similar to track bouncing in the analog world."

This way, it works.

So, is this (compositing) the right and the only one way?
How do we render two or more projects together (which way do we go....File; Render as or - compositing: Tools, Render to New Track....)?
Why does the procedure (file, render as) work well for the whole project (made up with 2 or more as described) with wmv and avi files?
Why does the procedure (file, render as) still woks with single projects for rendering as AVI and MPEG2?
Hope you can understand this. I know it's kind of confusing.
Thanks for your help.

Well, it's still a little confusing, but I'll try and clear some things up.

Firstly, the fact that Project 3 is made up of a combination of Projects 1 and 2 should make no difference to anything. Once the events are copied across, they still "point" to the same original media on the hard drive. If they do behave differently, it's probably because there are different settings somewhere.

Similarly, Render as and Render to new track are essentially the same process, they both create new video files which contain whatever was on the Timeline, the only difference being that Render to new track puts the new clip on new tracks on the timeline, lined up with the original content.

The fact that you are getting different results rendering to wmv, avi and MPEG2 suggests that your output settings are also different. (You didn't say what kind of avi you were trying to make.)
Personally I would first render to an avi using the default DV settings, then use this clip in a new project to create the wmv and MPEG2 versions. That way they should all behave the same, unless you're changing some settings which affect this.

hope this hasn't confused things even more .....

Not at all Peter. In fact, you understood everything. I can "render as" and the final result is: video delay. Now, if I "render to new track" there's no video delay. As I wrote before, video delay only happens when I render with the first process (file; render as). Anyway, for the avi file these are the settings I use for both processes (file; render as) - (tolls; render to new track);
NTSC DV
Project - Video rendering quality: best
Project - resample the framerate of all video

Audio - include audio checked.

thanks a lot

It seems I've got a problem around here. Don't know if it is with my windows or if I haven't learned how to render as MPEG2 files "with" video yet. It also seems nobody wants to discuss this...why? C'mon folks..........I'm waiting for some help...

I've posted this thread to get to know a bit more of "rendering".
For the AVI files:
I wrote before about AVI files. Now I can render both projects (1 and 2 both made up of jpeg files, titles and transitions) as AVI, separately, and later render again both as AVI (with no artifacts). On the other hand, if I render the project as a whole (1 and 2) made up of JPEG files and transitions (it's funny), some artifacts can be easily viewed around titles. To fix this, I cut the part corresponding to project 1 and paste another project 1 rendered separately. Is this the right way?
For the MPEG2 files:
As soon as I render MPEG2 files - both projects described above; JPEG files, etc, (I tried DVDArchitect NTSC video stream) at the end of the process when I view the file tru Windows Media Player, the audio does not match the video, that means, there's a delay for the video, because audio always seems to come first. Reading Vegas Help, about MPEG2 rendering process; I've found out this:
"You must render your audio separately in a format compliant with your specific DVD-authoring software. Consult your DVD-authoring software documentation to determine the supported audio formats."
Whould that be the answer I'm looking for?????????????????????????????????????????