Being ID user from its first incarnation I came across this problem for a first time.
Apparently I have a corrupted text frame that I can't touch in any way not to crash my InDesign. So trying to delete text, move the frame, resize, change attributes (columns) or even delete the page on which the frame sits causes a crash. Editing the frame's contents in Story Editor also crashes ID.
And even after exporting the document to IDML, deleting the frame on CS4/Windows proved successful, the InDesign CS5 didn't even open the modified doc and crashed straight away.
It may be, although I can't confirm it 100%, that this 'virus' came with the file from ID CS4 on my previous Windows machine.
Mac Pro, Mac OS X 10.6.4, 6GB RAM, CS5 Standard.
This could be anything that CS5 does not simply like.
Divide and Conquer, keep removing things from CS4 - (styles, swatches, frames, text, master pages etc.) and keep trying to open in CS5. At which point it doesn't crash, try and figure out what elements you last removed, and that's what caused the crash.
I had CS5 crash on me when the Preferences for autoflowing were switched on, for some reason the reflow text caused Indesign to crash. Once I switched this preference off it all worked fine.
So you have a bit of experimenting to do figure out exactly what is causing it to crash.
I've had cursed frames where somehow people were able to make a text from of a line (not type on path) which prevents the affected objects to be copied, but never unable to be deleted. It was quite a search and destroy mission to find out what it was, as it was intermingled with innocuous rules in a tabbed text chart. In InDesign CS4 it would crash the application on paste, every CS4 6.0, 6.0.2 and 6.0.4 installation in the building. CS5 this very same textbox can copy and paste without issue, but obviously is useless as a text frame.
I have a similar issue. I have a text frame in a particular ID CS5 document, which contains in-line anchored objects. These are simple, black and white, vector, closed caption icons, the kind you see in TV listings (a "CC" with a box around it). A few of these CC icons can be deleted; if I mouse over them the outline or points will light up, and I know it's not one of the cursed ones. But most of them cannot be selected at all, except in story editor where they show up as object symbols. Deleting them in the story editor, or deleting the whole line of text where they occur, or deleting the frame, or moving the frame, or deleting the page, or applying a new master page to the page ... all these will cause ID to immediately crash.
The publication was created in CS4, and this problem was never experienced over years of use in CS4. However, once it was upgraded to CS5, the gremlins within apparently awakened.
I am kind of in a jam now, because I cannot figure out how to update my publication. I need to change one of the lines that has a CC icon in it, because the TV program in that time slot has changed. I can change the type, but if I try to remove the CC icon, boooom! ID goes down in flames.
Any hints/tips would be most appreciated. I've tried story editor, select, direct select, text select, none of these have worked (they all result in a crash).
I have had this problem on ID4. It's always a text frame that I try to edit that crashes the program. I am going to try some of the ways that have been posted but have had success creating a new document and dragging the pages from the old file to the new file. The problem goes away immediately.
Hope that helps as an alternative.