[QUOTE=groceryjunkie2;2105627]HEY!!! I DO have a spare 10GB seagate I salvaged from an old tower, will that work???[/QUOTE]
This will work, but will probably be significantly slower than your current hard drive which will offset the advantage of having the paging file on a separate drive.
In terms of memory, open the case up and have a look at it; manufacturers have a nasty habit of filling all the available memory slots with small modules rather than one big one which would leave space for an upgrade. You might have to ditch your current memory and buy all new chips. If you’re lucky you can pull one of the current chips out and it’ll have a nice clear label identifying exactly what sort of RAM it is, but this is not always the case. Follow GJ’s link to your motherboard specs to find out exactly what sort of RAM you need and what combinations will be supported (some older MoBos required pairs of identical RAM chips).
As for buying RAM, I’d start at ebay, unless newegg are ridiculously cheap; RAM is pretty bullet proof; it either fails out of the box when new, or goes on indefinitely.