cannot choose os between win xp &ubuntu starts only in ubuntu cannot do anything i am really dissapointed

Thank you for taking the time to report this issue and helping to make Ubuntu better. Examining the information you have given us, this does not appear to be a bug report so we are closing it and converting it to a question in the support tracker. We appreciate the difficulties you are facing, but it would make more sense to raise problems you are having in the support tracker at https://answers.launchpad.net/ubuntu if you are uncertain if they are bugs. For help on reporting bugs, see https://help.ubuntu.com/community/ReportingBugs#When%20not%20to%20file%20a%20bug.

Sounds like you need to make grub stay onscreen longer. If you run:

gksudo gedit /boot/grub/menu.lst

you will see a timeout line which you can increase so grub stays onscreen longer. Reinstalling XP may have damaged things but I can't really comment on that without some other information.

It also sounds like you have given a very small amount of space to Ubuntu with your comment that you cannot install updates. This is not ubuntus fault but is your own as you are constraining ubuntu with so little space. You should uninstall big bulky apps like openoffice and gimp to freee up some space.

Can you please provide the output of:

sudo fdisk -l

so we can evaluate the space. Thanks.

Hi :)

This link might help
https://help.ubuntu.com/community/UsingTheTerminal#Starting%20a%20Terminal
then type in

sudo fdisk -l

where " -l" is a lower-case " -L" and the sudo command will ask for your normal user password, not your SuperUser/Root one and wont give you any stars as you type. Just copy & paste the output from that into here and we should be able to help

Good luck and regards from
Tom :)