scan freeze up never see a virus..or a bad thing at all..?

vista and chrome ive had 6 full loss crashes since october 11’ w/avast…cant get a full scan to not hang up…always a win sys or a avast file when occurring…never a single item detected…tried panda. eset all say ok no issues…why the slow freeze and hang ?also chrome hangs up when a scan is on…always

Please, check this file and send it (or them) to virus (at) avast (dot) com alerting that the scanning is facing problems while scanning it (them). Thanks.