Memory size

I think you can do this by Gparted program, or using property softwares like Acronis disk director.

Open your computer with Ubuntu 10.10 Live CD, and System > Administration > Gparted

Good luck, i hope this information is helpful for you.

No this didn't help. It won't allow me to change the memory in partition where is ubuntu

Do you use Wubi (Ubuntu installed inside Windows) or a true dual boot (Ubuntu and Windows side by side) ?

true dual boot

Do a BACKUP! Can be done after boot on Ubuntu CD, which avoid issues with copy of changing /home.
You must have done a true shutdown (no hibernation) on both Windows and Ubuntu.

Boot on Ubuntu CD.
Choose "Try without install".
System->Administration->Gparted.
Select partition to reduce and do a reduce/shift operation.
Select partition to increase and do a increase/shift operation.
If you have a swap partition between partition to reduce and increase, don't move this partition. Delete it, and rebuild it immediately after (swap partition, for virtual memory, hold no data).

Only the windows partition can be changed but not the ubuntu

On start i've tried like that, no problem... Ok let's make a new question. I will format all the pc and give and install ubuntu on hole memory, but i've download all the programs all thath i need for work on the old ubuntu. Can i after format without starting downloading again get back all my programs?

Thanks delance, that solved my question.