probably nothing I can do, but might as well ask....

Hello, This is my first time using this board, so hopefully someone can help. I have a house that was built in the mid 70's and has single pane aluminum windows. The inside is sheetrocked of course and the outside of the house is brick. OK, I would like to go to Home Depot or Lowes and get some double pane insulated windows, energy star rated and install. I have done many other things to the house, but never windows. I was told by one person that all I had to do was take a Saz-all and cut around the edge of the window from the inside to cut the fins off that were nailed to the 2x4's when it was built. Then pull out from inside and install new accordingly and caulk etc. Is this true? Are there other ways. Obvioulsy I don't want to take apart the brick. LOL I have read a couple other places that talk about the wood framed windows where they leave the window frame in place and then size the new one to fit there and secure and recaulk. Can this be done with the aluminum typw windows I have? Well any help would be appreciated. Thanks Dwayne Gulfport, Mississippi

We are considering replacing most of the windows in our house. They are about 40 years old and orignal to the house. I'm not exactly sure what type of windows they are but we turn a crank to open them. They do not seal very well and when we walk by, we can feel the air blowing through. They do have weatherstripping, but it doesn't seem to be doing the trick. They are very attractive,(three or four large panes of glass depending on the size of the window) but are not energy efficient. We have about 13 windows to deal with and they vary in size (roughly 52" X 50", 36" X 36", and 53" X 38"). Are there any projects we can do to these windows to extend their lives? We live in southern Mississippi and the climate is relatively mild in the winter, but summers are hot, hot, hot!