Quick googling shows F2 is 5400 RPM while the F3 is 7200 RPM. Not that I'm a hard drive expert, but instinct says to stay away from the F2
As for PSUs, you definitely
do not want a no-name PSU. For those you never know if the 750W really is 750W nor if it's going to stay the same when it gets older, not to mention some no-name PSUs exploding and stuff like that... The PSU I listed is really not expensive and is more than enough. I'd rather have reliable 525W than 750W that might turn out to be a lot less in reality (or after a year of usage).
If you don't want driver issues, just stick with winXP. If you want new stuff just save yourself the trouble and install 64 bit from the start (and on a partition that is just large enough to have OS and maybe some other basic MS stuff like office and have at least 50% free space left). I have my winXP installed on a 50GB partition and it has 30% free space, so even a 100-150GB partition for your OS can be an overkill, leaving quite a lot for your "everything else" partition in any case.