Modding your camera files for more control over cam moves and frames:

The original camera parameters are not adapted for movie making. It's too harsh and you can't frame properly. But you can mod it to your liking. I personally uses Gunmod's camera mod 3.1 as a base, and then changed a few mores changes using JayDee's and stormboy515's tutorials (stormboy515's tut is ment to let you shot some smooth camera moves).

Modding your video capture file to shot at a higher resolution and fps rate:

The in-game camera is very handy because, compared to outside capture software like Fraps, because it reccords what's on your screen without any pause bar or UI, and most of the time, cropping while editing is not necessary. But the largest settings only let you shoot at a 640x480 resolution, 15 fps. Good enough for youtube, but not that great if you want to make nicer, better quality movies. But you can change a few parameters in your VideoCapture.ini file (located in the MyDocuments/EA Games/The Sims 2/Config folder) to achieve that result. I personally shoot at 800x600, 25 fps (even though I render at a 720x576. This gives me more flexibility if I want to zoom and reframe a sequence a bit without quality loss). So here are the parameters I change:

LargeSettings = size: 800x600
MediumQualitySettings = minq: 4, maxq: 10, fps:25, mode:0
MediumHighSettings = datarate: 1000

Once in game, I shot at large size, medium quality (keeps large quality for when I want to experiment with 30fps and slow motion).
Now all you have to do is to mod this file to your needs (or you can download Delusion's video capture mod if you don't want to mess with the files yourself).

Also sometimes, when you enable anti-aliasing and try to shoot, the game tells you you can't. Just replace the zero by a one in the AllowAntialiasing=0 line to be able to shoot with AA on. And try to only enable AA just before shooting, because this precess is very heavy on the graphic card and it might over-heat if AA is on for too long

Important note: Your game will erase the VideoCapture.ini file each time it is launch, and will replace your settings by the default ones. You must alt-tab out of the game once it is fully loaded (you can also use the windows key), and then replace the new VideoCapture.ini by the one with your settings.

Take a serie of high resolution screenshots:

The game standard setting for large picture is 600x450 pixel. Which is too small if you want to take high quality pictures. As much as I know, there are no way to change the size of the in-game capture tool. However, you can use an external software to take high quality pics. I personally use Fraps, which is largely used inside the picture taking community. Unlike when filming, the free version of fraps does not watermark screenshots.
I know there are other softwares of the same style, but never really looked around for them as Fraps works great with me. You can also use the PrintScreen Key and alt-tab out of your game, but this is not the most convinient way if you want to take a serie of screens.

Converting a community lot into a residential lot:

As you know, it's much easier to film on community lots. But sometimes, you download the perfect restaurant set, and it's of course built on a community lot. To convert it into a residential and be able to move your cast (or extras) in, enter the lot, and enter that cheat "changelotzoning residential". You must place the public phoneand public trashcanby a mailbox and the residential trashcan before exiting so the game let you move sims in. You can download a collection containing those items at Sim a Little Dream a Lot (if you have Pets and/or seasons installed, you'll have to click the collection tab when you are in buildmode to be able to place those items).