So you need to press Cmd+Up. Yes, it's two keys instead of one but I would argue it's actually quicker since they are both usually located on the bottom row, meaning there is less distance for your hand to travel.
I just switched to OS X recently and I am definitely having the reverse trouble getting used to the Cmd/Alt+Arrow I almost never have problem finding Home/End on any keyboards (been using Windows/Linux for 15+ years). Nowadays for laptop it's almost always fn+Arrow for Home/End.
What do you mean some keyboards? Any PC keyboard you connect to the mac will support home, end, page up, etc. (Unlike buttons 4 and up on mice)
- Home (and Fn + Up) don't move your caret if you're in an editing context, except...
- Some apps have different behavior for Home than go-to-top. Typically these exceptions use the Windows behavior of go-to-start-of-line (obviously this does move your cursor).
I use space all the time to scroll down on a web page, didn't know you could reverse direction, awesome :)