I bought a new Canon 6D in December. I am currently editing in Lightroom 2. However, Lightroom 2 does not seem to be capable of reading my RAW files. I guess I need to upgrade to the latest version of Lightroom? If so, will the new version incorporate my existing images from Lightroom 2?
Yes, Lightroom 5 will allow you to continue to work with your existing images.
You could also download the free Adobe DNG converter and convert your RAWs to DNG, which can be read by LR 2.
For the record, the Canon 6D was first supported in Lightroom 4.3 (and later versions but not earlier ones).
Adobe only sells current versions of Lightroom (currently 5.7).
You can either pay a once off US$79 upgrade fee to upgrade from v.2 to v.5.7. See Products
Or subscribe to the Photography Plan ($10/month) and get all future updates and upgrades included in your membership
Or use the free Adobe DNG converter, convert all 6D Raw files to DNG format then edit in LR2