Add RAM?

Hello,
I have a 9 year old Gateway, desktop model 500x. Pentium 4 2.4GHz processor but only 256MB RAM. I was told this is WAY too little RAM and my slow speed seems to bear this out. 1.) Can I add RAM - I think there is an expansion slot 2.) Will it help? 3.) How much should I add? 4.) Where can I get it? 5.) Cost to purchase is about ???
Thank you in advance for your help of an old guy! PS - Haven't a clue what sub-category this should be so I just picked one. Sorry about that!

Well, with a system that dated adding nothing is really going to help. Everything is slow. I would suggest putting money into a new system.

Can't say I disagree with you - just trying to be cheap is all! But I did see a new desktop (at Bestbuy - can't remember which one) that showed just 2.2 gig processor. I am not looking for a rocket, just something I don't have to tweek daily with scrubs, defrag, etc. So is there any hope for me? Or am I just being dumb?

personally I think bestbuy is overpriced but here are some decent systems available from them

http://www.bestbuy.com/site/Asus+E [...] 4400050000 <- 4GB Ram, 2.8 GHZ dual core athlon xII, 750GB HDD, integrated graphics with a 20 inch LCD. 499.98

http://www.bestbuy.com/site/Asus+- [...] Id=4602619 <- same thing no monitor. 399.99

http://www.bestbuy.com/site/Asus+E [...] 4400050002 <- same thing bigger monitor (23.6 inch) and a printer/scanner. 559.99

http://www.bestbuy.com/site/Dell+- [...] Id=4673045 <- amd athlon x2 @ 3.0 GHZ, 4gb ram, 500gb HDD. 379.99

there are some pretty decent systems/combos out there, but you can get better for cheaper if you look.

http://www.newegg.com/Product/Prod [...] IsNodeId=1 <-- see what looks good here and ask and we will try to push you in the right direction