I need to get a handle on what options/companies I should consider for replacement windows. We have wood framed double-paned windows with broken seals. Not all the windows are operable (may be painted shut). Can I replace just the glass part or does the whole unit need to be replaced? Am I losing a lot of efficiency because of the broken seals (fogged glass)? The windows on the west side of the house must have condensation that builds on them because the blinds that have been covering them have some mold on them. Does this indicate a different type of window would work better on that side of the house? Any referrals to a great window place in the Seattle area?