Not that I'm trying to push you toward buying third-party apps, but shortly after I bought my MBP, I downloaded, installed, tried, and finally bought a substitute driver for the TrackPad called SideTrack, from RagingMenace:
http://ragingmenace.com/software/sidetrack/
It'll cost you 15 bucks (USD), but the developer is a really nice guy who actually answers to your email when you have questions about how to best use his application. Said application will let you completely customize your TrackPad, as it will for example allow you to assign a certain task to each corner of your TrackPad (eg, right-click for the upper-right corner, previous Web browser page for the lower-left corner, forward for the lower-right corner, etc...). Since I started using SideTrack, I rediscovered the simple joy of scrolling with one finger instead of two, and pointer erratic behaviors are a thing of the past.
You can try the app without buying it for a month, I think, but be careful, it's addictive!