Well, usually it tells me that I'm missing fonts and that I should purchase them on the internet. If I have the fonts it opens just like it does in 6 and 4.(I don't have 5)
That sounds pretty normal -- although it should still open the document with missing fonts -- the text of the missing fonts should just default to another font, like Monaco or something...
When I go to imput text, I receive a delayed response in the program and get multiple letters like: I'm haaaving a prrroblem with Quarrrk - as an example.
Strange... what kind of font management are you using? Suitcase? FontReserve? FontBook? Or are you just dragging and dropping fonts into the ~/Library/Fonts folder?