It should be helping a bit with multitasking as by setting aside with the recording then you can allocate cores to recording but at the same time it will be more harder for processor to work as it is 4 cores with 8 threads, but threads are like cores cutted into half so it wont be as that...
You'd have to change back to auto because IGP is builtin graphics on CPU which works from motherboard not gpu itself, and you need to connect DVI cable to GTX 750 not to motherboard.
It is because Windows 7 does not support GPT scheme therefore it is better to format HDD with clean windows 7 installation and if you can try to set bios to Legacy mode which and Windows 7 needs to have NTFS formation on HDD.
It depends, but 3.0 ghz would be moderate because Q6600 is being bottlenecked in manyways such as 2.4ghz and games require often 3ghz as minimum for today.
Back then Q6600 was considered as low-end Quad-core whilist Q9650 has more cache and is faster with 0.6GHz than Q6600 clocked at 2.4GHz. (Had experience with Q6600)