I think you may be confusing loading the information from the HD with repaint speed.

As with the Windows 7 start menu it uses GDI.

It should take basically 0 time to paint.  The only exception is opening and closing the menu constantly which can trigger it to refresh the list on the close which means you may then open it while this is taking place.  Regarding this we have made a small change to 1.03a which detects a few cases of duplicate refreshes.

As for the search results, they are simply limited by how fast the search results come back from the Search service.  The reason you may think it is repainting is because we paint it in parts, apps results first, then control panel etc.  This allows for a much faster response time than waiting for all the results.  Windows 7 works in a similar way.

Is there a specific time when you find it to be slow?

Repainting block by block is not a case of redrawing being slow, it is simply a feature to keep redraws to a minimum.  If you can show 20 items and typically it takes less than 150ms to get a full search then painting it as each group (programs, settings, documents, files etc) means you may get say 5 redraws vs 20.  This saves battery life on laptops, and produces quicker results even if your perception is that it is being slow simply because you see a gap between repaints.  In reality you get your results quicker.

On my own personal windows 7 machine I see a similar block repainting system and search results can be somewhat slower than the Start8 ones, it very much depends on what you have installed on the machine.

Do not worry though, we are always looking to improve performance in all areas and I will make a note to get somone to look if search performance can be tweaked further.

Regarding your crash, is that reproducable?  Is there anything in the event log that might be useful?