Natalie,
I've decided to use iWeb beccause of its easy way on talking with my Macs.
As the other said here, working with Photoshop / Slices makes it easier.
As the majority of the audience will be people using PC (sorry for them .... ) you should consider 2 things:
1- Everytime you design something test it on Safari changing on "Develop>User Agent>Internet Explorer 6 or 7 or 8 .....
2- To avoid the necessity for them to download the Quicktime Player to watch your videos, go to this link -
http://www.iwebunlimited.com/iwebtips/Entries/2009/8/22_19-_Shadowbox_in_iW... - and learn (it is very simple) how to embend your video as .flv and have a player in your site for them. At the link you will also get a lot of good tips;
3- Forget about .png files (for transparency). Make them jpeg . Internet Explorer doesn't like Alpha channels.
Another good site -
http://allaboutiweb.com/
MacBook Pro 17"
2.5 GHz Intel Core 2 Duo
4GB 667 MHz DDR2 SDRAM
(2) External HD LaCieMac (400/800 FW and USB)with 500GB -(2) USB External HD Western Digital (in cases) with 750GB
OS X 10.5.7
Final Cut Studio 2