Crestline window conversion

This is a complicated question. I'm not really sure what kind of window you have; "side-push" isn't a term I'm familiar with. Are you referring to a horizontal sliding window? That is to say, does your window sash move horizontally, left to right, when you open and close it? Or did you mean something else?

As for converting your window to another style, the answer to this question is usually "no." Now, there are some cases where it is possible, but it's not always advised. There are just too many complications that can pop up over the years. 

That said, I don't really know what you have, so I don't know if it's worth considering or not. If possible, I'd like photos of your window, as well as any balance system it uses (if any). Any other information you can give in general would help. The more detailed you are, the better. I'd rather have more information than necessary than not enough information.

Thanks for clarifying! I'm afraid that still doesn't tell me much else about your window. I'll definitely need some photos. I'd like to see the top of the sash to start. I'd also like you to remove the sash entirely and show us photos of the side jamb track and whatever balances are used to support it.