Making Two Work For One

I have a Core2Duo laptop that runs the two cores at 1.5 Ghz. It's unfortunately my only available computer at this time. The older games I like to play are not written to utilize 2 cores, but I would very much like to see this happen somehow. A single 1.5 Ghz cpu just doesn't cut it for Morrowind.

I already tweaked the crap out of my Vista installation and the games in question, so I am really not looking for any more advise there. What I want to know is if there is any way to let 2 cores 'act like one' or 'form óne virtual CPU', or something else along those lines.

While I quite get that software should needs special instructions if it were to handle the CPU's directly, I don't get why you can't have some seperate Windows (or otherwise software) component to effectively multiplexe these cores to serve a single need. Is there anything at all I can do to put the 2nd, idle core to use in an old game that isn't optimized to use multiple cores?

Perhaps it's a moot point, but it feels wasteful and unfair. An upgrade in CPU technology shouldn't be a downgrade for my favourite old software.