What stuff can safely be deleted/uninstalled from a fresh Windows 7 install?

"You might be pretty much stuck when it comes to reducing the size of the base install. Modern Windows variants keep the whole install set on disc (which is why you can install extra components post-install without putting the installation media back in) and this is quite a large block of data even though it is compressed. If you are running low on space already, you might have trouble later as patches and service packs often get kept too. Deleting any of this is very much not recommended.

If you have a 7 variant that includes the XP-in-a-VM-for-compatibility, getting rid of that might free a noticeable amount of space, but otherwise you are probably stuck.

Caveat: I don't have Windows 7 installed anywhere yet personally, so I'm talking from second- or third-hand generation knowledge and may therefore be not entirely right!"