None of the above... both the ruf and lotus take skill to control and use to their full extent. I suggest getting yourself the cheaper of the two zondas.
The zondas have the super car geometry that really makes the difference. With the zonda you get the power of a 12 cylinder and the control of a mid-engined supercar.
This is of course just my suggestion, but thats what it boils down to.
If the zonda is just too much money for you, than there are a few others I want to mention.
First on that list would be the s2000... you can get serious handling and about 530 hp with a pwr of something around 2.0. (plus you get that 9000rpm range)
Then there is the vette... simple said, you can get serious hp and even better, serious torque from a great v8.
Finally this brings us to the rufs.
All three have unique charactoristics and cover pretty much the entire spectrum of racers...
First off, the 3400, great all around car. Flat out. (powerful, well balanced, fully capable)
Second, the rgt... kinda like a monster version of the 3400. Much more powerful and much more capable. However, this car really takes some major skill to work the full capacity of its worth... so unless your a real pro, avoid it until your capable of handling a highly powered, rear engine, rear wheel drive car.
Finally, the ctr2... this is your car if your into major power and limited control. Great for the player who only wants straight line power and loves to bump their way through the turns rather than actually turn the car for themselves.
Anyway, I hope this helps to some extent. (just remember, these are only my feelings and Im no big shot here, so good luck and take everyones advice to mind.) (btw, the cars listed will all easily carry you through the beginner and amatuer levels of races, pro level races on the other hand... your gonna have to use a few of the better choices mentioned throughout the thread... the lotus, the rufs, the zondas... the zondas

)
later.