Which to put -> programs or files on faster drive?

I would install the OS on the faster drive, and the apps that you work the most with. Once a file is loaded into ram its not going to be constantly hitting the hard drive, until you go to save.

Following are a few tweaks you might consider:

1. Put the page file on a separate (fastest) HDD (not separate partition on the same HDD). Why? Seek time is a bottleneck; if data files and the page file are on different HDDs, the heads are not going back-and-forth between the two on the same HDD;

2. Defragment putting your most important files (and the page file on its separate disk) at the beginning of the disk. (Windows, by default, puts itself before anything else, including the page file, at the beginning of the disk);

3. Since you have plenty of RAM, set your page file size to one-half your RAM but set the max to approximately 3 times your amount of RAM.

Monk

partition your VR with a 100 and 200GB partition and put the OS and main apps on the 100GB partition and other apps on the 200GB partition.

your renderings and other files can go on the 750GB drive.

Before you follow all this excelleni advice given, you may want to test the speed of both disks with HDTune. Only if the access time of the new disk is noticeably better than the other disk will you see a performance improvement.