Yeah - the issue is less to do with Windows and everything to do with the original Skyrim being a 32-bit application. Like 32-bit Windows versions being limited to 4GB of memory ALL IN.
I'm not an expert but my understanding is enb could be used to increase what VRAM the system would use.
The other option is of course the 64-bit "Skyrim Enhanced" or whatever it's being called thats about to hit us in October - for some crazy reason I actually await it's arrival with a degree of anticipation - despite knowing that it's just going to be an even more polished version of the same turd - but I too have a occasional weakness for shiny things and at least on the surface - Skyrim gleams.
Edit:- Back in 2007 I bought a PC that had 64bit dual core 2GHZ AMD processor - I had an old Nvidia 8600 I think with a gig of VRAM and originally 4GB of ram - wasn't until 2010 I realised that the 32 bit version of Windows Vista meant that it was only using 3.5GB of the ram I had installed and 512MB of the VRAM on the card. I used to have a couple of tools for monitoring things but just thought maybe they were faulty figures I was getting - not understanding what was going on at all...... I then upgraded to Windows 7 64-bit, stuck another 4GB of ram in and it was like having a new machine. I've tried to educate myself somewhat since realising what a tube I'd been - although - why sell a PC with 64-bit processors with 32-bit OS was a bit out of order which means I build everything myself from scratch now as well.
Ignorance is most certainly not bliss.