>>Windows XP has built-in Remote Assistance support.
>
>Can my client see what i am doing? as she could guide me to the option where trobleshooting is needed.
>Is it always installed or does one need to install a windows component?
>
>Some of my clients are still running Win 98, any suggestion for that?
>
>Thanks.

Aman,
Check LogMeIn https://secure.logmein.com/
With it your customer can give you permission for remote desktop assistance.
He/She can not start the session, but He/She can stop that service and He/She can watch what are you doing during the session.
Supported window versions: Windows 98, 2000, XP, and Server 2003.