Performance implications of a large Documents folder

I have over time noticed a gradual degradation in computer performance, I cannot figure out what it is, and it being my office computer, I cannot run the usual tools to diagnose this problem (no admin privileges). IT department is always too "busy" to look into it.

The computer runs fine with CPU-intensive operations (compiling, image manipulation...etc.) but anything that requires more than the usual amount of disk activity (i.e. loading a program) takes a disproportionate amount of time to do so.

The only thing I can think of is the large documents folder that I have, and possibly the Windows search indexer going nuts over it.

My documents folder has ~900,000 files, 73,000 folders, and is 140GB large.

Moving those files to another location will take a couple of hours (yes, it's slow, that's my problem.) and, in total, take a day to re-setup my system into working condition.

So before I proceed with that, I would like to shoot out this quick question to see if I would be wasting my time doing that.

The problem, as @MonkeyZeus stated and as I tried to figure out, is free space.

Although you can run almost any OS with 0 KB of free space in the main disk (been there, done that, on both Vista and OSX), the system will suffer. Why?

There exists a reserved space called virtual memory (or paging file or swap partition), that serves as a pool of space to be used as memory for almost any application that exists. Why is it used instead of regular RAM? Performance: it is better to have the processes that use more memory more frequently on RAM rather than latent, check-once processes.

That space is somewhat variable, and the OS will try to achieve a balance (when in need) between used and virtual disk space. If programs can't store information on the disk, the only place that remains is the RAM. That will end up bottlenecking your entire system.

As you use somewhat intensive programs, that could be the main cause for your lack of performance.

The solution, as stated before, is to try and clear space. Outlook files, temporary files, cache files, duplicate files, all contribute to the lack of space. There is no one-size fits-all rule for these kinds of situation but clearing temporary folders is a good start.