Q: what do I need to make my system "current"?  MacOSX 10.5.8, P = 2.8ghz Intelcore 2 duo, M=26B 800 MHZ DDR2SDRAM

Make sure that you have a good backup just in case. I highly recommend making a CarbonCopyCloner or SuperDuper backup on a second external hard drive in leu-of or in addition to Time Machine.

1. Buy a Retail Snow Leopard 10.6 Upgrade.

http://www.apple.com/shop/product/MC573Z/A/mac-os-x-106-snow-leopard

2. Update Snow Leopard to 10.6.8 using the Combo Updater.

Mac OS X 10.6.8 Update Combo v1.1

3. Create an App Store Account.

Create an iTunes Store, App Store, or iBooks Store account without a credit card or other payment method - Apple Suppor…

4. Upgrade to the latest OS X El Capitan 10.11 which is free.

Upgrade to OS X El Capitan - Apple Support

Also worth noting at this point:

1. is that any PowerPC that you are currently using, will not longer work

2. with only 2 GB of RAM, you may also find that you need a RAM upgrade