Steam is the backbone of HL2 and all other source and online games released by Valve. No, there is no way around it. Since Steam will download to any computer, anywhere, DVD/CD back-up is unneccesary. There is an option to burn a backup under the properties of the game in steam. You still need to be online for it to work. Game specs say you need to have an internet connection under the term "required".
Activation is inevitable! For all other games I use my Plextor 716 A, Alcohol120% and Daemon Tools.

My Specs
Pentium D 830 (3.0GHZ on each core)
Dual Western Digital 7200 RPM SATAII 400GB Drives
Plextor 716 A DL DVD Burner
ATI Radeon X800 XL PCI X16
NEC DL Drive (no name from newegg)
Sceptor 20.1" 4x3 1600x1200 native resolution baby!!!
Haupague PVR 150
FOXCONN Serverboard with Dual GIGABIT LAN (1000Mbps)
Windows Media Center