Using Quicktime alone for streaming, rather than as a plugin in Firefox

There is a website where, up until a few days ago, I could watch the site's videos on Quicktime: when I clicked on the icon on the web page to view the video, Quicktime launched and I could view the video on Quicktime rather than in Firefox itself (and thus make it full screen size). I could even close out of Firefox and just keep Quicktime only and view the entire streaming video with no problems at all. However, a couple of days ago Quicktime failed to launch and I had to view the video (2" by 2" image that I can't make bigger) only on the website, in Firefox, and since then that has been the case. Other than manually plugging in the very long url into Quicktime and viewing it that way, which I've succeeded in doing, is there any way to 'force' Quicktime to 'take over' from Firefox when I want to view a streaming video? I didn't change any settings in either of Quicktime or Firefox. I have a 20" iMac with 2.4GHz and it's running on 10.5.1 (it's a great computer). Thank you for any help.

Do you have the same problem when using Safari?

Initially, when I first tried the new iMac, I tried using Safari, and the streaming image was about 2" by 2", which was the same size as on my previous iMac using Firefox, but it was more buggy so I went over to Firefox (the latest version) and, when I tried using Firefox, Quicktime opened and, after a few moments, started streaming the video, as if I had launched Quicktime in order to view the video. I was surprised and happy too since I was able to make the video (a daily news program) expand to screen size, which I could not do when trying to view the video on Safari or on my old iMac in Firefox or Safari. Then, when it 'reverted' to streaming only in the browser, I decided to try on my own to cut and paste the complete URL into the Quicktime Player (the 'Open URL...' command in 'File' in the menu) it worked fine - all I have to do is change the date to get each day's video. It's cumbersome and I wonder if there is a way to make Quick Time work automatically as before. Maybe the latest upgrade to QT (7.4.1 (14)) will make everything return to normal.

I was going to suggest that the website had changed their java script, but that wouldn't seem to fit with what you just said. If you have not changed any setting like you have already said, all I can think is that the latest patch to quicktime has altered the way it behaves with this website. You have been allowing your mac to do automatic updates right?

Yes, I do regular updates. I did update QuickTime and now everything is back to normal - if that is the proper word - , all by itself, until the next strange occurrence. Odd. I guess I'll have to find out about Java, since I barely know anything about Java other than it exists and is something that works in the web. Then I'll maybe be prepared for the next 'event'! Thank you for your help.