The HG 20 is merely an AVCHD camcorder
As such Regarding self biuld, you need a mid range Quad core with 3-4 Gb RAM and a decent Graphics card
Beyond that the permutations in hardware are endless
Sta HDD with without RAID ect
Nvidea or ATi mid range top end cards
There are a few threads here on PC capable of editing AVCHD , you might want to do a search and se what is on them
Simiarly AVCHD editing software abound. Virtualy most editing softwar out noww can edit AVCHD ad the diferences are in GUI and hardware requirements. The GI relates too to ease of use. most are learnable]
Search is your friend
Start from Here
http://www.avforums.com/forums/deskt...elf-build.html How's this for AVCHD editing?? Please recommend a good home movie editting programme AVCHD editing software choices Best Software To Edit AVCHD Footage?