No, you didn't manage to get a decent laptop (from a game playing point of view) back then. The 9300 M was merely a laptop version of the older 8400 GS, which when compared to game requirements, amounted to a total garbage piece of junk. The 9n00 cards came out a year after the 8n00 cards, which was four years ago. While Oblivion is quite old, the fact is that for its day, it had fairly strict requirements, and an 8400 GS just wasn't good enough, unless you obtained the Launcher from the 1.1 patch that added an "Ultra Low" graphics and resolution setting that didn't exist when the game was released (very muddy, and ugly looking, but it allowed the low quality cards like the 7300 GS and the 8400 GS to "sort of" play the game).

The 7300 GS was concurrent with Oblivion, six years ago, the 8400 GS came out five years ago, and the 9300 M was four years ago (not quite as "bad" because it benefited from a new, thinner die wafer). Newer products from three years ago included the Geforce GT 240 M, and the Geforce GTS 250 M, which were both quite decent.

Somewhere out there, someone still has a copy of the alternate version of the Options Menu with the Ultra Low choice still available. Running it down is where the problem comes in.