This isn't an exact science because it depends on screen resolution etc but here's a guideline:
Page type and dimensions (x,y – ie width/height in pixels)
Graphics - sound - 450 450
Column navigator - 2 cols - 300 x 300 / 3 cols - 230 230
Button navigator - 300 x 300
Tabbed navigator (text aligned top)
* small panel – 250 x 300
* medium panel 400x300
* large panel - 550x300
* full 700x300
Accordion navigator 4 panels
(4 panels gives 230 px height. Allow 20px height loss per additional panel – eg 6 panels max ht=230-40=190px)
* Small panels, no text 250x230
* Medium panels, no text – 400 x 230
* Large panels, no text – 550x230
* Full panel, no text – 700x230
Audio slideshow - 250x300
Morph image - 300x300 (automatically scaled)
Connector Hotspot image - 450 x 450 (image in textbox – 230x140 if no more than 1 line text). Won't rescale but will break box if too big.
Annotated diagram - 500x450
Drag and drop - 500x450
Hotspot image - 500x420
Quiz - 190x190
Interactive list - 300x300
Memory game - 100x130