I have Windows 7 64bit Build 7100 installed onto a HP NX7300 laptop and overall it runs well, except for a strange problem I've recently discovered with the start menu and the death of explorer.exe.
It's taken a while to replicate it reliably. Sorry if my terminology isn't right.
1) Press the Windows Key to open the start menu.
2) Make sure the mouse pointer is inside the thin blue strip at the top of the start menu, i.e. the frame.
3) Navigate to a menu entry which features a right hand sub menu (like Notepad and it's recent documents OR Getting Started and it's Tasks) using the cursor keys.
4) Navigate to the sub menu by using the right hand cursor key.
5) Move the mouse slightly to the left or right to ensure that none of the items in the sub menu are highlighted. Sometimes the submenu opens out like this without having to move the mouse.
6) Press the left cursor key to return to the previous part of the start menu. You'll hopefully notice that the item you'd expect to be highlighted (i.e. the one you moved right from) is not highlighted at all.
7) Press a left or right cursor key once more and explorer.exe hangs. Well.... it does for me. You should see the flashing caret freeze within the 'Search programs and files' box.
8) Attempts to click on the start menu/Windows icon result in the Explorer.exe has crashed, restart/close/wait message appearing.
Cheers!!