Update.
I bought a 250 GB Samsung SSD from Canada Computers on Wednesday. Since I have 6 SATA ports on my motherboard, I now have 3 drives in my computer with the old 160 GB OS drive as an eventual back up drive once have everything running properly. The new SSD and clean install does make a huge a difference and I'm very happy with my computer's speed. I'm not sure what effect the SSD has on video performance but I have no problem with viewing YouTube with 1080p instead of my previous limit of 720p.
Thanks for the great advice everyone. I'll next be working on making sure my computers are properly backed up.