What kind of video are you trying to add and what are you currently trying to do to add it?

Your menu is missing ending <li> tags which will cause IE to go into Quirks Mode and is likely causing any display issue. Run your page through a validator like this: http://validator.w3.org/ and take care of any errors first. If the display issue persists, then we can start looking deeper.

Quick note: A splash page as you have used is really not a good idea as far as search engine optimization goes and will likely result in your site being much lower in the list in any given search results than a site that doesn't use the splash page.

EDIT: If you want to have dummy links, use a single # as the link, instead of something like "Site Under Construction". Also, stay away from using spaces or special characters in page names. Use hyphens or underscores instead.

The link to your video is incorrect, or your video has been uploaded to the wrong folder. When I follow the link in the source to VIDEO0010.swf I get a 404 file not found error.

You need to go into your source code and delete the extra copies of your navigation menu css. From line 19 to line 739 looks like it would be safely deleted.

Line 19 needs to be deleted, it's just a left over ending style tag.

I assume you are talking about how the Contacts link in your menu drops to a second line?

Try changing...

.NavigationBarFixedCentered {

float: none;
width: 1000px;
margin-left:auto;
margin-right:auto;

to

.NavigationBarFixedCentered {

float: none;
width: 1011px;
margin-left:auto;
margin-right:auto;

You should look at creating a FLV video instead of a SWF as its a little more flexible with online video. You can then add a SWF player with controls. If you have Adobe Creative Suite, Adobe Media Encoder can take your AVI file and convert to FLV.

Alternatively, and possibly the best solution for iTouch devices and everything else, is to use a media player - like YouTube or JW Player - http://www.longtailvideo.com/players . This takes some of the hassle out.

Sorry, try 1012px, I think 1011 is 1 pixel too small.

All of those partial pixels (13.87775px and what-not)  in your CSS could be causing some of the problem.

Can you upload the page with the change?