Vista 64bit
Core 2 Duo T8300 2.4 GHz
4GB RAM
nVidia Geforce 8600M GS
not really sure how to find out my hard disk's rpm atm (I think it's 3200.. ), but it's 240GB
The video card is alright...good for about medium settings (1280x800 resolution). Performance issues can stem from quite a lot of different things. Some suggestions...
Vista Performance Guide:
http://www.gamesas.com/bgsforums/index.php?showtopic=762701&st=0
Performance Mods and Tweaks:
http://www.gamesas.com/bgsforums/index.php?showtopic=718322
Streamline
Operation Optimization
LowPolyGrass
Oblivion Polygone Overhaul
...are some noteworthy mods.
Your notebook should have at least a 5400rpm drive in this day and age.