Embodied conversation agents (ECAs) are increasingly being developed for older adults as assistants or companions. Older adults may not be familiar with ECAs, influencing uptake and acceptability. First impressions can correlate strongly with subsequent judgments, even of computer agents, and could influence acceptance. Using the circumplex model of affect, we developed three versions of an ECA -- laughing, smiling, and neutral in expression -- to evaluate how positive first impressions affect acceptance. Results from 249 older adults indicated no statistically significant effects except for general attitudes towards technology and intelligent agents. This questions the potential of laughter, jokes, puns, and smiles as a method of initial engagement for older adults.