I have an older Dell Inspiron 1150 laptop that I use for a few isolated things and tinkering. It runs XP Home Edition, Service pack 3. I'm going to add RAM and am wondering if it's possible to change the OS to Vista or Windows 7, and if so, what difference will it make?
Thanks for your help.

You are going to want to compare the OS system requirements to your specs.

Looking at the specs for your Dell 1150 and system requirements for Vista and Win 7 the only thing I noticed is your HD is only a 30 GB. Not enough to run Vista. Win 7 requires 16GB of available HD space. I haven't really compared anything else.


Dell Inspiron 1150 Specs - Laptops - CNET Reviews

Windows Vista system requirements - Microsoft Windows

Windows 7 system requirements - Microsoft Windows


As for the reasons to change to Vista or Win 7 see link below.

Windows XP vs Visa vs Windows 7? - Yahoo! Answers

Windows compared: Windows 7 vs Vista vs XP | News | TechRadar

probably easiest way to xheck is see if there are drivers on manufacturers website for vista or 7, if there are none it doesnt mean its impossible but it will give you an idea what your going to be up against.

Looking at the specs I do not know if another OS would serve you better or not. If you've only got a total of 30GB HD space, Windows 7 would eat up half of it. Not good. Also, I think your laptop's motherboad will only accept a total of 1GB RAM, and that is the minimum requirement for Win7.
The specs are the same for Vista.
It looks as though a larger hard drive needs to be considered as well.
Personally, I think a bare minimum of 2GB RAM is needed for Vista or Win7 to run well.
But that's just me.

IIRC that is an intel 945 graphics card with a Pentium 4 chip. If you can get more than 1gb of ram in it the machine should run ok. However if it maxes out at 1gb you are better off sticking with xp or replacing the machine.

Check it out on crucial.com