Upgrading from Windows XP to Windows 7<<- is a common Google term.
If you want several links, just copy and paste this term into your Google browser, and there are many ideas.
The one I linked above also contains the; Is your present hardware / software compatible with windows 7 item included in it.
With only 960mb ram
I think a dual boot is a bit out of the question at this time
, but may be an option later.
You seem to only just have enough space for a single boot now, so I still use my link when I install Win 7 on an XP based unit -
Plenty of good reading material for you in both posts, so please look them over and then make a final decision
Good luck on your adventure -