Well thats strange that the updates are taking up so much space. Normally when you install updates it will remove whatever old files/programs it is replacing but there shouldn't be a change in your gig's..... Are you sure about the gig difference?

When I get the update reminder it's usually when I'm turning it off It tells me WIndows is ready/Windows has found an update would you like to install now or later? (If you install now Windows will automatically shut down once finished) I always click update but I've never seen a big change in my drive as far as gig's.

Well you can only ignore the updates for so long cause sometimes you'll wan't to open a link or sometype of file and your version of java or something like that won't support it...... If I'm not mistaken you can google 'Latest Windows Update' and download that and install it see if that works......