Looks like it's been a few months, so you may have this resolved by now. If that's not the case, however, I'll give you some insight on your problem.
The message 'side by side configuration is incorrect' usually refers to an incompatible framework. I believe (although I don't use Visual Studio 2005) that your compiler uses the .NET frame 2.0, which can be useful if you're developing cross platform. One quick way to solve your problem is, find out which framework you compiled with, and install the .NET framework 'redist' package on the computer you want to run the plugin. You should be able to find the redist package on the Microsoft website.
It's also possible that you'll be able to find a project setting in VC++ 2005 that lets you turn off the .NET framework compilation (again, not sure since I don't use that compiler). If you want to be able to sell and/or distribute your plugin, you probably want to get rid of the .NET framework one way or another. I mainly work in Windows, and personally, I haven't found much use for Visual Studio. It's always throwing in .NET, steering you toward cumbersome libraries like MFC and languages like c#, and each version gives you less and less freedom. If you take my advice, you'll go with an open source compiler like CodeBlocks.
Open source software may not be as sparkling easy as Visual Studio, but it's both reliable and flexible, actually giving you complete control over your compiled software. By default, it uses the GCC compiler, which is a free, non-Microsoft program. For compiling Maya plugins, however, you're actually going to need a Microsoft compiler, which is slightly more tricky to set up. I just went through the process a couple months ago, so if you want to try it out, save yourself some trouble and let me know so I can give you step by step instructions on how to set it up