Monaco lost me the world championship. My best performance there was fifth in the first season of my career, in the Super Aguri. That was a difficult race, but I did have to drive the last stint without a front wing in order to maintain the position. Since then, I've only ever scored DNFs. 
But yeah. If I'd finished in the points at Monaco in the last season I did, I'd have been champion. Although I guess I could have done better in Malaysia - wet weather driving is not my strong-point at all. :/
I was getting bored by S5, I'd won all the titles so far (That game is ridiculously easy on all settings, I think the PSP one must be easier by far than the PS2/3 versions, cos I didn't find it hard at all...Painful though). So I was like "Right, no more effing around, time to win 'em all". Took some doing what with bad luck and so on, but I got it done.
Really wish I'd stayed in the Honda. I won 2 Titles at the wheel of a Honda (And I was driving one at the end of S1). But for S4 I was poached by Renault - and naturally, won them two titles.
I've only ever done a couple of seasons. I have to admit, my first season with Super Aguri was the most fun. Finishing in the points in Bahrain, Australia, San Marino, Monaco, Hungary and Suzuka in such a horrible car felt like far more of an achievement than winning races in cars like the Williams and Toyota. They were some pretty good results, to be honest - making the most of a one-stop strategy is quite difficult! Dealing with completely-worn tyres in this game is challenging.
Results for that season (yes, I wrote them down because I'm sad) in full:
Bahrain: 8th
Malaysia: DNF (Wet)
Australia: 8th
San Marino: 6th
Europe: 16th
Spain: 19th
Monaco: 5th
Britain: DNF (Wet)
Canada: 11th
USA: 14th
France: 9th*
Germany: 15th
Hungary: 7th
Turkey: DNF
Italy: 9th
China: 11th**
Japan: 4th (Wet)
Brazil: 17th
Total points: 16
So, all-in-all, not so bad for Hard mode. I imagine the PSP version must be easier, 'cause on the PS2 the AI are pretty quick. They do, however, lack a decent amount of aggression and for the first lap it's easy to pass several cars (I usually made up four to six places on the starts, which was usually the reason I ended up in the points).
* Would have finished 7th but for a last-lap accident. Tried to brake late enough to pass Fisichella for another position but clouted the back of his car, lost the front wing and struggled for the rest of the lap with massive oversteer, ending up off-track several times.
** Would've finished 8th but for a stupid mistake that I can blame nobody other than myself for. I just forgot to brake in to turn one with ten laps to go and could not recover over the remaining laps.