Liteインスコしたんで表示された注意書きをば。 IMPORTANT: Diskeeper Lite includes the same advanced defragmentation technology used in Diskeeper full version. This program is the fastest defragmentation program ever built. Full version Diskeeper has 5 priority levels and can be easily set to run transparently in the background, even during peak production times. However, Diskeeper Lite is locked at the "normal" system priority level and may slow other online operations.
Set it and forget itが使えないのと、プロセス優先度がnormalにロックされてるため他の作業に悪影響を 与える恐れがある点以外はフル版と同じだそうだ。