If this is for gaming drop down the RAM and CPU to the i5 2500k and 8GB (2x4gb). Its pointless to get an i7 when the gaming capabilities are almost the exact same. Gaming doesnt benefit from 16GB of ram as well.
Go with a Z68 Motherboard I find them to be better than P67s
Here is a 1.5K build I was working on, drop the SSD if you want to bump up the GPU (not everyone needs one). The 750W PSU will be able to SLI/CF and OC with headroom left over and I got you a 23" monitor
Most programs that don't have a 64-bit counterpart will just install and run at 32-bit. I switched to 64-bit and didn't lose any programs along the way. As far as drivers, pretty much everything comes with a 64-bit driver now.
For the video card, have you considered EVGA instead of MSI? I am looking at a very similar budget and parts list for my system and was opting for the EVGA. It's the slightest bit cheaper, and has a lifetime warranty while the MSI has 3 years.
Some of the other parts you've listed are also available a little bit cheaper on Amazon, fyi. For instance, they have Corsair 2x4Gb DDR3 1600 for $35, whereas the G.Skill you have listed are $45. Just something to consider.
EDIT: Tried to find the link for it, but can't seem to. Perhaps it was a sale that is no longer available. If you search for it, you might be able to find it?
Also, have you considered any of the VelociRaptor 10,000rpm HDDs? The performance increase might be beneficial for you.