[Owen Phillips] "Is there anything I can do to get better results, or is it simply a case of my notebook not being up to scratch in terms of the power or graphics card?"
It looks like it's simply a case of your laptop not being powerful enough for HD video. The Pentium Dual Core was replaced by the Core 2 Duo, which was replaced by the Core i5/i7 so you are two generations behind. Also, laptop processors are rated very differently so that a T4000 series 2.2Ghz is way slower than a T9000 2.2Ghz. You may have to just live with it if you're not willing to buy a laptop that is powerful enough to edit HD. I would recommend a new Core i5 at a bare minimum.
~jr
http://www.johnrofrano.com
http://www.vasst.com 
