Your choice of colours is, of course, up to you. I do however suggest using a maximum pallet of 265 colours only for any images your create. Many people using the Internet have computers that will display a maximum of 256 colours. The Internet uses a palette of 216 colours for GIF style artwork, so if your image editing software supports this palette range use it for GIF pictures. If you want your page to be attractive to these people as well, you need to take this into account.
Photos are a bit different.
I have found that photos darken a bit when viewed by a browser, so lighten your photo a bit more than you need to give a better balance of colour brightness. These frames split the screen up into areas so that you can, for example, continue to have an index on one part of your screen and the information you're looking at in another. This means you don't have to keep clicking on Back to get back to the index. When using frames, give a thought to the people who are still using older programs like Internet Explorer 2 and older versions of Netscape, and there are many, many thousands of them. If you don't, they won't see much at all, if anything.