i have linux, also use comcast who doesnt recognize it, keeps telling me to upgrade, is there a way to put windows on toooo. really frustrated with linux.

You mean comcast cable internet? My cable internet doesn't matter what's plugged into the modem...

If you want to put on Windows, just buy a Windows installation CD and install it to your computer. Note that it usually prefers to be on the first primary partition, which usually means re-installing linux after you install Windows.

It doesn't matter what operating system you run to use cable internet, they don't need to recognize your os to have internet.

By not recognising linux, you mean that there techs dont know it and cant help you or you cant browse with linux?...

i have experienced this with my old service provider, there tech told me that they dont have linux or use it, funny thing was there servers are all linux, but thats another point... The techs are usually people that have a win back ground only and have no knowledge, let alone know what it is, of linux....
They train them with the basics of setting up a connection, and if your lucky, one may know more than just a network connection...
I would be inclined to ask the tech to pass you thru to one of there server techs, when you have problems...
I have yet to come across a connection that linux cant make, but i have come across a lot that believe windows is the internet and linux is just a toy...

You may just have to ask the right questions, and use that info to change your linux settings, anything from windows can be utilised with linux, if you get the right answers...