IDE is unbearably slow at compiling sketches, no matter what their length is

Today I started playing with my XDRduino Mega 2560 which I bought to see if this sort of something was my cup of tea. I already have quite a bit of programming experience, but my only achievement within the software-communicating-with-hardware world is that I have created an RFID check-in system for a local LAN party using the ACR122S and ACR122U card readers; I've mostly just made applications and dynamic websites before.

Let me start by saying that everything works as such. The problem is that the IDE takes, oh, 15-20 minutes to compile even a 10-line sketch, whether it is uploading or just verifying (on the plus side, a large sketch doesn't actually take any longer). The sketch DOES get uploaded, but I am dreading the feeling of having to wait 20 minutes just to see if changing that one character will make the sketch work. I have googled the issue, but all I get are posts about disabling bluetooth to make the IDE start faster, which is not the problem at all. It starts so fast I can barely see the splash screen, and it is extremely responsive, except when compiling. It also doesn't seem to matter if the XDRduino is connected or not, except of course that the upload fails (but the compilation still takes a full eon to complete), so I will not hesitate to say that the fact that it's only a clone is not the cause of the issue.

I am using a computer with Windows 8.1. The computer is incomprehensibly fast at all other tasks, so there is no bottleneck there.

Please advise.

On older OSs, having bluetooth stuff open killed performance.
Maybe that is an issue still?

The Arduino has it's own sub-set of Java.
Did you install Java ? please remove everything. You might also remove Arduino (but not your projects folder) and reinstall Arduino.
There is also a new beta version of Arduino you might want to try.
You can have more than one Arduino installed, by unzipping it in different locations. Just set the right project folder in the settings and you are good to go.

Bluetooth is definitely not the problem (the computer doesn't have it). Upgrading to 1.5.7 did fix the problem, it now compiles and uploades in perhaps 20 seconds (a sixty-fold improvement!). However, as is to be expected in the programming world, I have encountered other issues that may require the attention of this forum. Thank you for your help so far.