Well, if you want it to be the best quality then you should use 300 dpi Images. When you place an Image you can view the DPI in the Windows>Info pallet, you can see there how many DPI your images are.
If you need to resize an image make sure that it doesn't go under 225 dpi, view the info pallet, you can go above 300 dpi as much as you like, but that will make for larger file size and ultimately a slower work flow.
The images you place won't appear high quality because the images that InDesign show you are only placeholders, thumbnails created by InDesign to simulate the design. If you want to view the quality of your images, then choose,
View>Display Performance>High Quality
Change back to Typical Display to continue working and to save on memory for your computer.
Once you have your type set and your images placed and you're layout done.
You should File>Export>PDF
Ask your printing company what the best PDF settings you should use, most printing places will have their own settings and can talk you through them.
Other than that, everything will be fine using InDesign and High Quality.