tell me
to answer your question ... a machine designed for ME isn't up to the job of running a modern Os whether it's ... ubuntu whoareyou XP or anything else
moore's law states that processors double in speed about every 18 months .... how many 18 months have passed since you bought your old klunker?
how big is your HDD? at that spec we are probably less than 40 ... could well even be less than 10Gb
it will run it ... just - but especially if you are banking you need a virus scanner, an adware scanner ... a firewall ... all running together ... and that's where you'll hit problems
An old car is a wonderful thing to play with ... but can you imagine using a moggie 1000 every day?
If you want a machine for your goldfish ... hang on to it
For �200 you can buy a machine that is so much better than what you have now
Do you really want to put a lot of effort into learning a new Os?
Linux is fine if you want to play with OSs ... It's a techies Os ... if it takes 2000 lines of code to do something windows does in a click ... so much the better ....
and on a safety point ... linux was only safe because it's users weren't worth bothering about (not because it's well made)
linux is known to have over 800 vulnerabilities which no one has bothered to fix
http://insecure.org/sploits_linux.html
http://secunia.com/advisories/product/22/?task =statistics_2008