As time passes, there is always some advancement in technology. The time when windoxs XP was launched, it was considered to be the best OS of that time, and now when When windows 7 was launched it has more fans. No doubt, Windows 8 has already come and also it will be having great features.
Since the question is Which is better ? Windows XP or Windows 7.
According to me. It depends on system configuration and user using it. If you have a system with good configuration, it will be worth giving a try to Windows 7. It will work great. As far as windows XP is considered, I think it is simpler to use. A new user can easily interact with it's feature and can get familiar to it in shorter time as compared to windows 7.
But I personally recommend using window 7. Because it has stronger security from virus, other hacks...
More or less it finally depends on you, what type of environment you get and finally your system configuration.
Thanks and Regards,