i'm big on utilities and have tried literally hundreds the last couple of years.
free ones are hard to find, search for them on download.com is a good place.
but easycleaner 2.0 ...which is basically the same as ccleaner is good freebie
most registry cleaners arnt very thorough, some finds more than others, system suite has the best one and always finds at least 200 more junk entries than others.
i dont think much of system mechanic 5...has a slow defragger, its antispyware is worthless so is its firewall,antivirus...stripped down old version of kapersky
its other features can be found in free progs, its registry cleaner is certainly no better than ccleaners
to replace features in system mech i'd try
easycleaner or ccleaner
avast av or avg
adaware/spybot antispyware
gamexp and/or safexp
tcp tweaker or whatever its called
o&o defrag or power defrag