Order Agent, to answer your questions:
I am running Freelancer on an Athlon 1200 with a Geforce 2 MX400 and 3/4 GB RAM. Even though this system is not new, it is still well above the requirements for the game.
Some mission data and results can be seen here (converted to jpg to save bandwidth):
http://home3.inet.tele.dk/aolesen/screen4.jpg (difficulty 35)
http://home3.inet.tele.dk/aolesen/screen5.jpg (difficulty 35)
http://home3.inet.tele.dk/aolesen/screen7.jpg (difficulty 35)
http://home3.inet.tele.dk/aolesen/screen8.jpg (difficulty 36)
Opponents were mostly Class 9 ships on these missions. I have on other occassions beaten Sabres. Cannot remember if I have beaten Titans.
After a level 35-36 mission I need a lot of repair - at least when I survive.
After normal travelling in hostile border world systems I am not repairing much - mostly radiation damage.
I have not modded the game. I use a normal Class 6 Graviton shield.
I will not claim next that I have killed Nomads. I have already claimed it, since you cannot complete SP without encountering a lot of Nomads.
If you have any other questions, I will be glad to answer.